diff --git a/cef_paths2.gypi b/cef_paths2.gypi
index 1c5663d55..10e5a696a 100644
--- a/cef_paths2.gypi
+++ b/cef_paths2.gypi
@@ -470,6 +470,7 @@
       'tests/ceftests/browser_info_map_unittest.cc',
       'tests/ceftests/command_line_unittest.cc',
       'tests/ceftests/cookie_unittest.cc',
+      'tests/ceftests/cors_unittest.cc',
       'tests/ceftests/devtools_message_unittest.cc',
       'tests/ceftests/dialog_unittest.cc',
       'tests/ceftests/display_unittest.cc',
diff --git a/libcef/browser/alloy/alloy_content_browser_client.cc b/libcef/browser/alloy/alloy_content_browser_client.cc
index 1c0679cff..6c1664e19 100644
--- a/libcef/browser/alloy/alloy_content_browser_client.cc
+++ b/libcef/browser/alloy/alloy_content_browser_client.cc
@@ -1255,6 +1255,7 @@ void AlloyContentBrowserClient::RegisterNonNetworkSubresourceURLLoaderFactories(
       extensions::Manifest::IsComponentLocation(extension->location())) {
     // Components of chrome that are implemented as extensions or platform apps
     // are allowed to use chrome://resources/ and chrome://theme/ URLs.
+    // See also HasCrossOriginWhitelistEntry.
     allowed_webui_hosts.emplace_back(content::kChromeUIResourcesHost);
     allowed_webui_hosts.emplace_back(chrome::kChromeUIThemeHost);
   }
diff --git a/libcef/browser/net_service/proxy_url_loader_factory.cc b/libcef/browser/net_service/proxy_url_loader_factory.cc
index 131d3031e..bc52039a5 100644
--- a/libcef/browser/net_service/proxy_url_loader_factory.cc
+++ b/libcef/browser/net_service/proxy_url_loader_factory.cc
@@ -6,7 +6,9 @@
 #include "libcef/browser/net_service/proxy_url_loader_factory.h"
 
 #include "libcef/browser/context.h"
+#include "libcef/browser/origin_whitelist_impl.h"
 #include "libcef/browser/thread_util.h"
+#include "libcef/common/net/scheme_registration.h"
 #include "libcef/common/net_service/net_service_util.h"
 
 #include "base/barrier_closure.h"
@@ -19,6 +21,7 @@
 #include "mojo/public/cpp/base/big_buffer.h"
 #include "net/http/http_status_code.h"
 #include "services/network/public/cpp/cors/cors.h"
+#include "services/network/public/cpp/features.h"
 
 namespace net_service {
 
@@ -27,6 +30,26 @@ namespace {
 // User data key for ResourceContextData.
 const void* const kResourceContextUserDataKey = &kResourceContextUserDataKey;
 
+base::Optional<std::string> GetHeaderString(
+    const net::HttpResponseHeaders* headers,
+    const std::string& header_name) {
+  std::string header_value;
+  if (!headers || !headers->GetNormalizedHeader(header_name, &header_value)) {
+    return base::nullopt;
+  }
+  return header_value;
+}
+
+bool IsOutOfBlinkCorsEnabled() {
+  static int state = -1;
+  if (state == -1) {
+    state = base::FeatureList::IsEnabled(network::features::kOutOfBlinkCors)
+                ? 1
+                : 0;
+  }
+  return !!state;
+}
+
 }  // namespace
 
 // Owns all of the ProxyURLLoaderFactorys for a given BrowserContext. Since
@@ -219,6 +242,8 @@ class InterceptedRequest : public network::mojom::URLLoader,
                       bool wait_for_loader_error);
 
   void SendErrorAndCompleteImmediately(int error_code);
+  void SendErrorStatusAndCompleteImmediately(
+      const network::URLLoaderCompletionStatus& status);
 
   void SendErrorCallback(int error_code, bool safebrowsing_hit);
 
@@ -366,6 +391,27 @@ void InterceptedRequest::Restart() {
   current_request_uses_header_client_ =
       !!factory_->url_loader_header_client_receiver_;
 
+  if (IsOutOfBlinkCorsEnabled() && request_.request_initiator &&
+      network::cors::ShouldCheckCors(request_.url, request_.request_initiator,
+                                     request_.mode)) {
+    if (scheme::IsCorsEnabledScheme(request_.url.scheme())) {
+      // Add the Origin header for CORS-enabled scheme requests.
+      request_.headers.SetHeaderIfMissing(
+          net::HttpRequestHeaders::kOrigin,
+          request_.request_initiator->Serialize());
+    } else if (!HasCrossOriginWhitelistEntry(
+                   *request_.request_initiator,
+                   url::Origin::Create(request_.url))) {
+      // Fail requests if a CORS check is required and the scheme is not CORS
+      // enabled. This matches the error condition that would be generated by
+      // CorsURLLoader::StartRequest in the network process.
+      SendErrorStatusAndCompleteImmediately(
+          network::URLLoaderCompletionStatus(network::CorsErrorStatus(
+              network::mojom::CorsError::kCorsDisabledScheme)));
+      return;
+    }
+  }
+
   const GURL original_url = request_.url;
 
   factory_->request_handler_->OnBeforeRequest(
@@ -881,10 +927,12 @@ void InterceptedRequest::ContinueToResponseStarted(int error_code) {
   override_headers_ = nullptr;
   redirect_url_ = GURL();
 
+  scoped_refptr<net::HttpResponseHeaders> headers =
+      current_response_ ? current_response_->headers : nullptr;
+
   std::string location;
-  const bool is_redirect = redirect_url.is_valid() ||
-                           (current_response_->headers &&
-                            current_response_->headers->IsRedirect(&location));
+  const bool is_redirect =
+      redirect_url.is_valid() || (headers && headers->IsRedirect(&location));
   if (stream_loader_ && is_redirect) {
     // Redirecting from OnReceiveResponse generally isn't supported by the
     // NetworkService, so we can only support it when using a custom loader.
@@ -903,6 +951,30 @@ void InterceptedRequest::ContinueToResponseStarted(int error_code) {
     LOG_IF(WARNING, is_redirect) << "Redirect at this time is not supported by "
                                     "the default network loader.";
 
+    // CORS check for requests that are handled by the client. Requests handled
+    // by the network process will be checked there.
+    if (IsOutOfBlinkCorsEnabled() && stream_loader_ && !is_redirect &&
+        request_.request_initiator &&
+        network::cors::ShouldCheckCors(request_.url, request_.request_initiator,
+                                       request_.mode)) {
+      const auto error_status = network::cors::CheckAccess(
+          request_.url,
+          GetHeaderString(
+              headers.get(),
+              network::cors::header_names::kAccessControlAllowOrigin),
+          GetHeaderString(
+              headers.get(),
+              network::cors::header_names::kAccessControlAllowCredentials),
+          request_.credentials_mode, *request_.request_initiator);
+      if (error_status &&
+          !HasCrossOriginWhitelistEntry(*request_.request_initiator,
+                                        url::Origin::Create(request_.url))) {
+        SendErrorStatusAndCompleteImmediately(
+            network::URLLoaderCompletionStatus(*error_status));
+        return;
+      }
+    }
+
     // Resume handling of client messages after continuing from an async
     // callback.
     if (proxied_client_binding_)
@@ -992,7 +1064,13 @@ void InterceptedRequest::CallOnComplete(
 }
 
 void InterceptedRequest::SendErrorAndCompleteImmediately(int error_code) {
-  status_ = network::URLLoaderCompletionStatus(error_code);
+  SendErrorStatusAndCompleteImmediately(
+      network::URLLoaderCompletionStatus(error_code));
+}
+
+void InterceptedRequest::SendErrorStatusAndCompleteImmediately(
+    const network::URLLoaderCompletionStatus& status) {
+  status_ = status;
   SendErrorCallback(status_.error_code, false);
   target_client_->OnComplete(status_);
   OnDestroy();
diff --git a/libcef/browser/origin_whitelist_impl.cc b/libcef/browser/origin_whitelist_impl.cc
index 6bd3bca6a..1a8c74923 100644
--- a/libcef/browser/origin_whitelist_impl.cc
+++ b/libcef/browser/origin_whitelist_impl.cc
@@ -15,8 +15,12 @@
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/synchronization/lock.h"
+#include "chrome/common/webui_url_constants.h"
 #include "content/public/browser/render_process_host.h"
+#include "content/public/common/url_constants.h"
+#include "extensions/common/constants.h"
 #include "url/gurl.h"
+#include "url/origin.h"
 
 namespace {
 
@@ -157,10 +161,11 @@ CefOriginWhitelistManager* CefOriginWhitelistManager::GetInstance() {
   return g_manager.Pointer();
 }
 
-bool IsMatch(const GURL& source_origin,
-             const GURL& target_origin,
+bool IsMatch(const url::Origin& source_origin,
+             const url::Origin& target_origin,
              const Cef_CrossOriginWhiteListEntry_Params& param) {
-  if (source_origin.GetOrigin() != GURL(param.source_origin)) {
+  if (!source_origin.IsSameOriginWith(
+          url::Origin::Create(GURL(param.source_origin)))) {
     // Source origin does not match.
     return false;
   }
@@ -271,7 +276,18 @@ void GetCrossOriginWhitelistEntries(
       entries);
 }
 
-bool HasCrossOriginWhitelistEntry(const GURL& source, const GURL& target) {
+bool HasCrossOriginWhitelistEntry(const url::Origin& source,
+                                  const url::Origin& target) {
+  // Components of chrome that are implemented as extensions or platform apps
+  // are allowed to use chrome://resources/ and chrome://theme/ URLs.
+  // See also RegisterNonNetworkSubresourceURLLoaderFactories.
+  if (source.scheme() == extensions::kExtensionScheme &&
+      target.scheme() == content::kChromeUIScheme &&
+      (target.host() == chrome::kChromeUIThemeHost ||
+       target.host() == content::kChromeUIResourcesHost)) {
+    return true;
+  }
+
   std::vector<Cef_CrossOriginWhiteListEntry_Params> params;
   CefOriginWhitelistManager::GetInstance()->GetCrossOriginWhitelistEntries(
       &params);
diff --git a/libcef/browser/origin_whitelist_impl.h b/libcef/browser/origin_whitelist_impl.h
index bca948c2d..3136cad1c 100644
--- a/libcef/browser/origin_whitelist_impl.h
+++ b/libcef/browser/origin_whitelist_impl.h
@@ -12,7 +12,9 @@ namespace content {
 class RenderProcessHost;
 }
 
-class GURL;
+namespace url {
+class Origin;
+}
 
 struct Cef_CrossOriginWhiteListEntry_Params;
 
@@ -23,6 +25,7 @@ void GetCrossOriginWhitelistEntries(
 
 // Returns true if |source| can access |target| based on the cross-origin white
 // list settings.
-bool HasCrossOriginWhitelistEntry(const GURL& source, const GURL& target);
+bool HasCrossOriginWhitelistEntry(const url::Origin& source,
+                                  const url::Origin& target);
 
 #endif  // CEF_LIBCEF_BROWSER_ORIGIN_WHITELIST_IMPL_H_
diff --git a/libcef/common/alloy/alloy_main_delegate.cc b/libcef/common/alloy/alloy_main_delegate.cc
index 6b585a3ac..23e573927 100644
--- a/libcef/common/alloy/alloy_main_delegate.cc
+++ b/libcef/common/alloy/alloy_main_delegate.cc
@@ -244,12 +244,6 @@ bool AlloyMainDelegate::BasicStartupComplete(int* exit_code) {
 
     std::vector<std::string> disable_features;
 
-    if (network::features::kOutOfBlinkCors.default_state ==
-        base::FEATURE_ENABLED_BY_DEFAULT) {
-      // TODO: Add support for out-of-Blink CORS (see issue #2716)
-      disable_features.push_back(network::features::kOutOfBlinkCors.name);
-    }
-
 #if defined(OS_WIN)
     if (features::kCalculateNativeWinOcclusion.default_state ==
         base::FEATURE_ENABLED_BY_DEFAULT) {
diff --git a/libcef/common/net/scheme_registration.cc b/libcef/common/net/scheme_registration.cc
index cd67ae05c..b34eb9704 100644
--- a/libcef/common/net/scheme_registration.cc
+++ b/libcef/common/net/scheme_registration.cc
@@ -8,6 +8,7 @@
 #include "libcef/common/net/scheme_info.h"
 #include "libcef/features/runtime.h"
 
+#include "base/stl_util.h"
 #include "content/public/common/url_constants.h"
 #include "extensions/common/constants.h"
 #include "net/net_buildflags.h"
@@ -86,4 +87,10 @@ bool IsStandardScheme(const std::string& scheme) {
   return url::IsStandard(scheme.c_str(), scheme_comp);
 }
 
+// Should return the same value as SecurityOrigin::isLocal and
+// SchemeRegistry::shouldTreatURLSchemeAsCorsEnabled.
+bool IsCorsEnabledScheme(const std::string& scheme) {
+  return base::Contains(url::GetCorsEnabledSchemes(), scheme);
+}
+
 }  // namespace scheme
diff --git a/libcef/common/net/scheme_registration.h b/libcef/common/net/scheme_registration.h
index c8064fd9e..dcbdbb671 100644
--- a/libcef/common/net/scheme_registration.h
+++ b/libcef/common/net/scheme_registration.h
@@ -22,6 +22,9 @@ bool IsInternalHandledScheme(const std::string& scheme);
 // Returns true if the specified |scheme| is a registered standard scheme.
 bool IsStandardScheme(const std::string& scheme);
 
+// Returns true if the specified |scheme| is a registered CORS enabled scheme.
+bool IsCorsEnabledScheme(const std::string& scheme);
+
 }  // namespace scheme
 
 #endif  // CEF_LIBCEF_COMMON_NET_SCHEME_REGISTRATION_H_
diff --git a/tests/ceftests/cors_unittest.cc b/tests/ceftests/cors_unittest.cc
new file mode 100644
index 000000000..bbd736bc0
--- /dev/null
+++ b/tests/ceftests/cors_unittest.cc
@@ -0,0 +1,983 @@
+// Copyright (c) 2020 The Chromium Embedded Framework Authors. All rights
+// reserved. Use of this source code is governed by a BSD-style license that
+// can be found in the LICENSE file.
+
+#include <algorithm>
+#include <vector>
+
+#include "include/base/cef_bind.h"
+#include "include/cef_callback.h"
+#include "include/cef_origin_whitelist.h"
+#include "include/cef_scheme.h"
+#include "include/wrapper/cef_closure_task.h"
+#include "tests/ceftests/routing_test_handler.h"
+#include "tests/ceftests/test_request.h"
+#include "tests/ceftests/test_server.h"
+#include "tests/ceftests/test_util.h"
+
+namespace {
+
+const char kMimeTypeHtml[] = "text/html";
+const char kMimeTypeText[] = "text/plain";
+
+const char kDefaultHtml[] = "<html><body>TEST</body></html>";
+const char kDefaultText[] = "TEST";
+
+const char kSuccessMsg[] = "CorsTestHandler.Success";
+const char kFailureMsg[] = "CorsTestHandler.Failure";
+
+// Source that will handle the request.
+enum class HandlerType {
+  SERVER,
+  HTTP_SCHEME,
+  CUSTOM_STANDARD_SCHEME,
+  CUSTOM_NONSTANDARD_SCHEME,
+};
+
+std::string GetOrigin(HandlerType handler) {
+  switch (handler) {
+    case HandlerType::SERVER:
+      return test_server::kServerOrigin;
+    case HandlerType::HTTP_SCHEME:
+      return "http://corstest.com";
+    case HandlerType::CUSTOM_STANDARD_SCHEME:
+      // Standard scheme that is CORS and fetch enabled.
+      // Registered in scheme_handler_unittest.cc.
+      return "customstdfetch://corstest";
+    case HandlerType::CUSTOM_NONSTANDARD_SCHEME:
+      // Non-sandard scheme that is not CORS or fetch enabled.
+      // Registered in scheme_handler_unittest.cc.
+      return "customnonstd:corstest";
+  }
+  NOTREACHED();
+  return std::string();
+}
+
+std::string GetPathURL(HandlerType handler, const std::string& path) {
+  return GetOrigin(handler) + path;
+}
+
+struct Resource {
+  // Uniquely identifies the resource.
+  HandlerType handler = HandlerType::SERVER;
+  std::string path;
+
+  // Response information that will be returned.
+  CefRefPtr<CefResponse> response;
+  std::string response_data;
+
+  // Expected error code in OnLoadError.
+  cef_errorcode_t expected_error_code = ERR_NONE;
+
+  // Expected number of responses.
+  int expected_response_ct = 1;
+
+  // Expected number of OnQuery calls.
+  int expected_success_query_ct = 0;
+  int expected_failure_query_ct = 0;
+
+  // Actual number of responses.
+  int response_ct = 0;
+
+  // Actual number of OnQuery calls.
+  int success_query_ct = 0;
+  int failure_query_ct = 0;
+
+  Resource() {}
+  Resource(HandlerType request_handler,
+           const std::string& request_path,
+           const std::string& mime_type = kMimeTypeHtml,
+           const std::string& data = kDefaultHtml,
+           int status = 200) {
+    Init(request_handler, request_path, mime_type, data, status);
+  }
+
+  // Perform basic initialization.
+  void Init(HandlerType request_handler,
+            const std::string& request_path,
+            const std::string& mime_type = kMimeTypeHtml,
+            const std::string& data = kDefaultHtml,
+            int status = 200) {
+    handler = request_handler;
+    path = request_path;
+    response_data = data;
+    response = CefResponse::Create();
+    response->SetMimeType(mime_type);
+    response->SetStatus(status);
+  }
+
+  // Validate expected initial state.
+  void Validate() const {
+    DCHECK(!path.empty());
+    DCHECK(response);
+    DCHECK(!response->GetMimeType().empty());
+    DCHECK_EQ(0, response_ct);
+    DCHECK_GE(expected_response_ct, 0);
+  }
+
+  std::string GetPathURL() const { return ::GetPathURL(handler, path); }
+
+  // Returns true if all expectations have been met.
+  bool IsDone() const {
+    return response_ct == expected_response_ct &&
+           success_query_ct == expected_success_query_ct &&
+           failure_query_ct == expected_failure_query_ct;
+  }
+
+  void AssertDone() const {
+    EXPECT_EQ(expected_response_ct, response_ct) << GetPathURL();
+    EXPECT_EQ(expected_success_query_ct, success_query_ct) << GetPathURL();
+    EXPECT_EQ(expected_failure_query_ct, failure_query_ct) << GetPathURL();
+  }
+
+  // Optionally override to verify request contents.
+  virtual bool VerifyRequest(CefRefPtr<CefRequest> request) const {
+    return true;
+  }
+};
+
+struct TestSetup {
+  // Available resources.
+  typedef std::vector<Resource*> ResourceList;
+  ResourceList resources;
+
+  // Used for testing received console messages.
+  std::vector<std::string> console_messages;
+
+  void AddResource(Resource* resource) {
+    DCHECK(resource);
+    resource->Validate();
+    resources.push_back(resource);
+  }
+
+  void AddConsoleMessage(const std::string& message) {
+    DCHECK(!message.empty());
+    console_messages.push_back(message);
+  }
+
+  Resource* GetResource(const std::string& url) const {
+    if (resources.empty())
+      return nullptr;
+
+    const std::string& path_url = test_request::GetPathURL(url);
+    ResourceList::const_iterator it = resources.begin();
+    for (; it != resources.end(); ++it) {
+      Resource* resource = *it;
+      if (resource->GetPathURL() == path_url)
+        return resource;
+    }
+    return nullptr;
+  }
+
+  Resource* GetResource(CefRefPtr<CefRequest> request) const {
+    return GetResource(request->GetURL());
+  }
+
+  // Validate expected initial state.
+  void Validate() const { DCHECK(!resources.empty()); }
+
+  std::string GetMainURL() const { return resources.front()->GetPathURL(); }
+
+  // Returns true if the server will be used.
+  bool NeedsServer() const {
+    ResourceList::const_iterator it = resources.begin();
+    for (; it != resources.end(); ++it) {
+      Resource* resource = *it;
+      if (resource->handler == HandlerType::SERVER)
+        return true;
+    }
+    return false;
+  }
+
+  // Returns true if all expectations have been met.
+  bool IsDone() const {
+    ResourceList::const_iterator it = resources.begin();
+    for (; it != resources.end(); ++it) {
+      Resource* resource = *it;
+      if (!resource->IsDone())
+        return false;
+    }
+    return true;
+  }
+
+  void AssertDone() const {
+    ResourceList::const_iterator it = resources.begin();
+    for (; it != resources.end(); ++it) {
+      (*it)->AssertDone();
+    }
+  }
+};
+
+class TestServerObserver : public test_server::ObserverHelper {
+ public:
+  typedef base::Callback<bool()> CheckDoneCallback;
+
+  TestServerObserver(TestSetup* setup,
+                     const base::Closure& ready_callback,
+                     const base::Closure& done_callback)
+      : setup_(setup),
+        ready_callback_(ready_callback),
+        done_callback_(done_callback),
+        weak_ptr_factory_(this) {
+    DCHECK(setup);
+    Initialize();
+  }
+
+  ~TestServerObserver() override { done_callback_.Run(); }
+
+  void OnInitialized(const std::string& server_origin) override {
+    CEF_REQUIRE_UI_THREAD();
+    ready_callback_.Run();
+  }
+
+  bool OnHttpRequest(CefRefPtr<CefServer> server,
+                     int connection_id,
+                     const CefString& client_address,
+                     CefRefPtr<CefRequest> request) override {
+    CEF_REQUIRE_UI_THREAD();
+    Resource* resource = setup_->GetResource(request);
+    if (!resource) {
+      // Not a request we handle.
+      return false;
+    }
+
+    resource->response_ct++;
+    EXPECT_TRUE(resource->VerifyRequest(request))
+        << request->GetURL().ToString();
+    test_server::SendResponse(server, connection_id, resource->response,
+                              resource->response_data);
+
+    // Stop propagating the callback.
+    return true;
+  }
+
+  void OnShutdown() override {
+    CEF_REQUIRE_UI_THREAD();
+    delete this;
+  }
+
+ private:
+  TestSetup* const setup_;
+  const base::Closure ready_callback_;
+  const base::Closure done_callback_;
+
+  base::WeakPtrFactory<TestServerObserver> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestServerObserver);
+};
+
+class CorsTestHandler : public RoutingTestHandler {
+ public:
+  explicit CorsTestHandler(TestSetup* setup) : setup_(setup) {
+    setup_->Validate();
+  }
+
+  void RunTest() override {
+    StartServer(base::Bind(&CorsTestHandler::TriggerCreateBrowser, this));
+
+    // Time out the test after a reasonable period of time.
+    SetTestTimeout();
+  }
+
+  // Necessary to make the method public in order to destroy the test from
+  // ClientSchemeHandlerType::ProcessRequest().
+  void DestroyTest() override {
+    EXPECT_TRUE(shutting_down_);
+
+    setup_->AssertDone();
+    EXPECT_TRUE(setup_->console_messages.empty())
+        << "Did not receive expected console message: "
+        << setup_->console_messages.front();
+
+    RoutingTestHandler::DestroyTest();
+  }
+
+  void DestroyTestIfDone() {
+    CEF_REQUIRE_UI_THREAD();
+    if (shutting_down_)
+      return;
+
+    if (setup_->IsDone()) {
+      shutting_down_ = true;
+      StopServer();
+    }
+  }
+
+  CefRefPtr<CefResourceHandler> GetResourceHandler(
+      CefRefPtr<CefBrowser> browser,
+      CefRefPtr<CefFrame> frame,
+      CefRefPtr<CefRequest> request) override {
+    CEF_REQUIRE_IO_THREAD();
+    Resource* resource = setup_->GetResource(request);
+    if (resource && resource->handler != HandlerType::SERVER) {
+      resource->response_ct++;
+      EXPECT_TRUE(resource->VerifyRequest(request))
+          << request->GetURL().ToString();
+      return test_request::CreateResourceHandler(resource->response,
+                                                 resource->response_data);
+    }
+    return RoutingTestHandler::GetResourceHandler(browser, frame, request);
+  }
+
+  void OnLoadEnd(CefRefPtr<CefBrowser> browser,
+                 CefRefPtr<CefFrame> frame,
+                 int httpStatusCode) override {
+    const std::string& url = frame->GetURL();
+    Resource* resource = GetResource(url);
+    if (!resource)
+      return;
+
+    const int expected_status = resource->response->GetStatus();
+    if (url == main_url_ || expected_status != 200) {
+      // Test that the status code is correct.
+      EXPECT_EQ(expected_status, httpStatusCode) << url;
+    }
+
+    TriggerDestroyTestIfDone();
+  }
+
+  void OnLoadError(CefRefPtr<CefBrowser> browser,
+                   CefRefPtr<CefFrame> frame,
+                   ErrorCode errorCode,
+                   const CefString& errorText,
+                   const CefString& failedUrl) override {
+    Resource* resource = GetResource(failedUrl);
+    if (!resource)
+      return;
+
+    const cef_errorcode_t expected_error = resource->response->GetError();
+
+    // Tests sometimes also fail with ERR_ABORTED.
+    if (!(expected_error == ERR_NONE && errorCode == ERR_ABORTED)) {
+      EXPECT_EQ(expected_error, errorCode) << failedUrl.ToString();
+    }
+
+    TriggerDestroyTestIfDone();
+  }
+
+  bool OnQuery(CefRefPtr<CefBrowser> browser,
+               CefRefPtr<CefFrame> frame,
+               int64 query_id,
+               const CefString& request,
+               bool persistent,
+               CefRefPtr<Callback> callback) override {
+    Resource* resource = GetResource(frame->GetURL());
+    if (!resource)
+      return false;
+
+    if (request.ToString() == kSuccessMsg ||
+        request.ToString() == kFailureMsg) {
+      callback->Success("");
+      if (request.ToString() == kSuccessMsg)
+        resource->success_query_ct++;
+      else
+        resource->failure_query_ct++;
+      TriggerDestroyTestIfDone();
+      return true;
+    }
+    return false;
+  }
+
+  bool OnConsoleMessage(CefRefPtr<CefBrowser> browser,
+                        cef_log_severity_t level,
+                        const CefString& message,
+                        const CefString& source,
+                        int line) override {
+    bool expected = false;
+    if (!setup_->console_messages.empty()) {
+      std::vector<std::string>::iterator it = setup_->console_messages.begin();
+      for (; it != setup_->console_messages.end(); ++it) {
+        const std::string& possible = *it;
+        const std::string& actual = message.ToString();
+        if (actual.find(possible) == 0U) {
+          expected = true;
+          setup_->console_messages.erase(it);
+          break;
+        }
+      }
+    }
+
+    EXPECT_TRUE(expected) << "Unexpected console message: "
+                          << message.ToString();
+    return false;
+  }
+
+ protected:
+  void TriggerCreateBrowser() {
+    main_url_ = setup_->GetMainURL();
+    CreateBrowser(main_url_);
+  }
+
+  void TriggerDestroyTestIfDone() {
+    CefPostTask(TID_UI, base::Bind(&CorsTestHandler::DestroyTestIfDone, this));
+  }
+
+  void StartServer(const base::Closure& next_step) {
+    if (!CefCurrentlyOn(TID_UI)) {
+      CefPostTask(TID_UI,
+                  base::Bind(&CorsTestHandler::StartServer, this, next_step));
+      return;
+    }
+
+    if (!setup_->NeedsServer()) {
+      next_step.Run();
+      return;
+    }
+
+    // Will delete itself after the server stops.
+    server_ = new TestServerObserver(
+        setup_, next_step, base::Bind(&CorsTestHandler::StoppedServer, this));
+  }
+
+  void StopServer() {
+    CEF_REQUIRE_UI_THREAD();
+    if (!server_) {
+      DCHECK(!setup_->NeedsServer());
+      DestroyTest();
+      return;
+    }
+
+    // Results in a call to StoppedServer().
+    server_->Shutdown();
+  }
+
+  void StoppedServer() {
+    CEF_REQUIRE_UI_THREAD();
+    server_ = nullptr;
+    DestroyTest();
+  }
+
+  Resource* GetResource(const std::string& url) const {
+    Resource* resource = setup_->GetResource(url);
+    EXPECT_TRUE(resource) << url;
+    return resource;
+  }
+
+  TestSetup* setup_;
+  std::string main_url_;
+  TestServerObserver* server_ = nullptr;
+  bool shutting_down_ = false;
+
+  IMPLEMENT_REFCOUNTING(CorsTestHandler);
+  DISALLOW_COPY_AND_ASSIGN(CorsTestHandler);
+};
+
+// JS that results in a call to CorsTestHandler::OnQuery.
+std::string GetMsgJS(const std::string& msg) {
+  return "window.testQuery({request:'" + msg + "'});";
+}
+
+std::string GetSuccessMsgJS() {
+  return GetMsgJS(kSuccessMsg);
+}
+std::string GetFailureMsgJS() {
+  return GetMsgJS(kFailureMsg);
+}
+
+std::string GetDefaultSuccessMsgHtml() {
+  return "<html><body>TEST<script>" + GetSuccessMsgJS() +
+         "</script></body></html>";
+}
+
+}  // namespace
+
+// Verify the test harness for server requests.
+TEST(CorsTest, BasicServer) {
+  TestSetup setup;
+  Resource resource(HandlerType::SERVER, "/CorsTest.BasicServer");
+  setup.AddResource(&resource);
+
+  CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);
+  handler->ExecuteTest();
+  ReleaseAndWaitForDestructor(handler);
+}
+
+// Like above, but also send a query JS message.
+TEST(CorsTest, BasicServerWithQuery) {
+  TestSetup setup;
+  Resource resource(HandlerType::SERVER, "/CorsTest.BasicServerWithQuery",
+                    kMimeTypeHtml, GetDefaultSuccessMsgHtml());
+  resource.expected_success_query_ct = 1;
+  setup.AddResource(&resource);
+
+  CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);
+  handler->ExecuteTest();
+  ReleaseAndWaitForDestructor(handler);
+}
+
+// Verify the test harness for http scheme requests.
+TEST(CorsTest, BasicHttpScheme) {
+  TestSetup setup;
+  Resource resource(HandlerType::HTTP_SCHEME, "/CorsTest.BasicHttpScheme");
+  setup.AddResource(&resource);
+
+  CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);
+  handler->ExecuteTest();
+  ReleaseAndWaitForDestructor(handler);
+}
+
+// Like above, but also send a query JS message.
+TEST(CorsTest, BasicHttpSchemeWithQuery) {
+  TestSetup setup;
+  Resource resource(HandlerType::HTTP_SCHEME,
+                    "/CorsTest.BasicHttpSchemeWithQuery", kMimeTypeHtml,
+                    GetDefaultSuccessMsgHtml());
+  resource.expected_success_query_ct = 1;
+  setup.AddResource(&resource);
+
+  CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);
+  handler->ExecuteTest();
+  ReleaseAndWaitForDestructor(handler);
+}
+
+// Verify the test harness for custom standard scheme requests.
+TEST(CorsTest, BasicCustomStandardScheme) {
+  TestSetup setup;
+  Resource resource(HandlerType::CUSTOM_STANDARD_SCHEME,
+                    "/CorsTest.BasicCustomStandardScheme");
+  setup.AddResource(&resource);
+
+  CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);
+  handler->ExecuteTest();
+  ReleaseAndWaitForDestructor(handler);
+}
+
+// Like above, but also send a query JS message.
+TEST(CorsTest, BasicCustomStandardSchemeWithQuery) {
+  TestSetup setup;
+  Resource resource(HandlerType::CUSTOM_STANDARD_SCHEME,
+                    "/CorsTest.BasicCustomStandardSchemeWithQuery",
+                    kMimeTypeHtml, GetDefaultSuccessMsgHtml());
+  resource.expected_success_query_ct = 1;
+  setup.AddResource(&resource);
+
+  CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);
+  handler->ExecuteTest();
+  ReleaseAndWaitForDestructor(handler);
+}
+
+namespace {
+
+std::string GetIframeMainHtml(const std::string& iframe_url,
+                              const std::string& sandbox_attribs) {
+  return "<html><body>TEST<iframe src=\"" + iframe_url + "\" sandbox=\"" +
+         sandbox_attribs + "\"></iframe></body></html>";
+}
+
+std::string GetIframeSubHtml() {
+  // Try to script the parent frame, then send the SuccessMsg.
+  return "<html><body>TEST<script>try { parent.document.body; } catch "
+         "(exception) { console.log(exception.toString()); }" +
+         GetSuccessMsgJS() + "</script></body></html>";
+}
+
+bool HasSandboxAttrib(const std::string& sandbox_attribs,
+                      const std::string& attrib) {
+  return sandbox_attribs.find(attrib) != std::string::npos;
+}
+
+void SetupIframeRequest(TestSetup* setup,
+                        const std::string& test_name,
+                        HandlerType main_handler,
+                        Resource* main_resource,
+                        HandlerType iframe_handler,
+                        Resource* iframe_resource,
+                        const std::string& sandbox_attribs) {
+  const std::string& base_path = "/" + test_name;
+
+  // Expect a single iframe request.
+  iframe_resource->Init(iframe_handler, base_path + ".iframe.html",
+                        kMimeTypeHtml, GetIframeSubHtml());
+
+  // Expect a single main frame request.
+  const std::string& iframe_url = iframe_resource->GetPathURL();
+  main_resource->Init(main_handler, base_path, kMimeTypeHtml,
+                      GetIframeMainHtml(iframe_url, sandbox_attribs));
+
+  if (HasSandboxAttrib(sandbox_attribs, "allow-scripts")) {
+    // Expect the iframe to load successfully and send the SuccessMsg.
+    iframe_resource->expected_success_query_ct = 1;
+
+    const bool has_same_origin =
+        HasSandboxAttrib(sandbox_attribs, "allow-same-origin");
+    if (!has_same_origin ||
+        (has_same_origin &&
+         (main_handler == HandlerType::CUSTOM_NONSTANDARD_SCHEME ||
+          main_handler != iframe_handler))) {
+      // Expect parent frame scripting to fail if:
+      // - "allow-same-origin" is not specified;
+      // - the main frame is a non-standard scheme (e.g. CORS disabled);
+      // - the main frame and iframe origins don't match.
+      // The reported origin will be "null" if "allow-same-origin" is not
+      // specified, or if the iframe is hosted on a non-standard scheme.
+      const std::string& origin =
+          !has_same_origin ||
+                  iframe_handler == HandlerType::CUSTOM_NONSTANDARD_SCHEME
+              ? "null"
+              : GetOrigin(iframe_handler);
+      setup->AddConsoleMessage("SecurityError: Blocked a frame with origin \"" +
+                               origin +
+                               "\" from accessing a cross-origin frame.");
+    }
+  } else {
+    // Expect JavaScript execution to fail.
+    setup->AddConsoleMessage("Blocked script execution in '" + iframe_url +
+                             "' because the document's frame is sandboxed and "
+                             "the 'allow-scripts' permission is not set.");
+  }
+
+  setup->AddResource(main_resource);
+  setup->AddResource(iframe_resource);
+}
+
+}  // namespace
+
+// Test iframe sandbox attributes with different origin combinations.
+#define CORS_TEST_IFRAME(test_name, handler_main, handler_iframe,     \
+                         sandbox_attribs)                             \
+  TEST(CorsTest, Iframe##test_name) {                                 \
+    TestSetup setup;                                                  \
+    Resource resource_main, resource_iframe;                          \
+    SetupIframeRequest(&setup, "CorsTest.Iframe" #test_name,          \
+                       HandlerType::handler_main, &resource_main,     \
+                       HandlerType::handler_iframe, &resource_iframe, \
+                       sandbox_attribs);                              \
+    CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup); \
+    handler->ExecuteTest();                                           \
+    ReleaseAndWaitForDestructor(handler);                             \
+  }
+
+// Test all origin combinations (same and cross-origin).
+#define CORS_TEST_IFRAME_ALL(name, sandbox_attribs)                            \
+  CORS_TEST_IFRAME(name##ServerToServer, SERVER, SERVER, sandbox_attribs)      \
+  CORS_TEST_IFRAME(name##ServerToHttpScheme, SERVER, HTTP_SCHEME,              \
+                   sandbox_attribs)                                            \
+  CORS_TEST_IFRAME(name##ServerToCustomStandardScheme, SERVER,                 \
+                   CUSTOM_STANDARD_SCHEME, sandbox_attribs)                    \
+  CORS_TEST_IFRAME(name##ServerToCustomNonStandardScheme, SERVER,              \
+                   CUSTOM_NONSTANDARD_SCHEME, sandbox_attribs)                 \
+  CORS_TEST_IFRAME(name##HttpSchemeToServer, HTTP_SCHEME, SERVER,              \
+                   sandbox_attribs)                                            \
+  CORS_TEST_IFRAME(name##HttpSchemeToHttpScheme, HTTP_SCHEME, HTTP_SCHEME,     \
+                   sandbox_attribs)                                            \
+  CORS_TEST_IFRAME(name##HttpSchemeToCustomStandardScheme, HTTP_SCHEME,        \
+                   CUSTOM_STANDARD_SCHEME, sandbox_attribs)                    \
+  CORS_TEST_IFRAME(name##HttpSchemeToCustomNonStandardScheme, HTTP_SCHEME,     \
+                   CUSTOM_NONSTANDARD_SCHEME, sandbox_attribs)                 \
+  CORS_TEST_IFRAME(name##CustomStandardSchemeToServer, CUSTOM_STANDARD_SCHEME, \
+                   SERVER, sandbox_attribs)                                    \
+  CORS_TEST_IFRAME(name##CustomStandardSchemeToHttpScheme,                     \
+                   CUSTOM_STANDARD_SCHEME, HTTP_SCHEME, sandbox_attribs)       \
+  CORS_TEST_IFRAME(name##CustomStandardSchemeToCustomStandardScheme,           \
+                   CUSTOM_STANDARD_SCHEME, CUSTOM_STANDARD_SCHEME,             \
+                   sandbox_attribs)                                            \
+  CORS_TEST_IFRAME(name##CustomStandardSchemeToCustomNonStandardScheme,        \
+                   CUSTOM_STANDARD_SCHEME, CUSTOM_NONSTANDARD_SCHEME,          \
+                   sandbox_attribs)                                            \
+  CORS_TEST_IFRAME(name##CustomNonStandardSchemeToServer,                      \
+                   CUSTOM_NONSTANDARD_SCHEME, SERVER, sandbox_attribs)         \
+  CORS_TEST_IFRAME(name##CustomNonStandardSchemeToHttpScheme,                  \
+                   CUSTOM_NONSTANDARD_SCHEME, HTTP_SCHEME, sandbox_attribs)    \
+  CORS_TEST_IFRAME(name##CustomNonStandardSchemeToCustomStandardScheme,        \
+                   CUSTOM_NONSTANDARD_SCHEME, CUSTOM_STANDARD_SCHEME,          \
+                   sandbox_attribs)                                            \
+  CORS_TEST_IFRAME(name##CustomNonStandardSchemeToCustomNonStandardScheme,     \
+                   CUSTOM_NONSTANDARD_SCHEME, CUSTOM_NONSTANDARD_SCHEME,       \
+                   sandbox_attribs)
+
+// Everything is blocked.
+CORS_TEST_IFRAME_ALL(None, "")
+
+// JavaScript execution is allowed.
+CORS_TEST_IFRAME_ALL(AllowScripts, "allow-scripts")
+
+// JavaScript execution is allowed and scripting the parent is allowed for
+// same-origin only.
+CORS_TEST_IFRAME_ALL(AllowScriptsAndSameOrigin,
+                     "allow-scripts allow-same-origin")
+
+namespace {
+
+struct SubResource : Resource {
+  SubResource() {}
+
+  std::string main_origin;
+  bool supports_cors = false;
+  bool is_cross_origin = false;
+
+  void InitCors(HandlerType main_handler, bool add_header) {
+    // Origin is always "null" for non-standard schemes.
+    main_origin = main_handler == HandlerType::CUSTOM_NONSTANDARD_SCHEME
+                      ? "null"
+                      : GetOrigin(main_handler);
+
+    // True if cross-origin requests are allowed. XHR requests to non-standard
+    // schemes are not allowed (due to the "null" origin).
+    supports_cors = handler != HandlerType::CUSTOM_NONSTANDARD_SCHEME;
+    if (!supports_cors) {
+      // Don't expect the xhr request.
+      expected_response_ct = 0;
+    }
+
+    // True if the request is considered cross-origin. Any requests between
+    // non-standard schemes are considered cross-origin (due to the "null"
+    // origin).
+    is_cross_origin = main_handler != handler ||
+                      (main_handler == HandlerType::CUSTOM_NONSTANDARD_SCHEME &&
+                       handler == main_handler);
+
+    if (is_cross_origin && add_header) {
+      response->SetHeaderByName("Access-Control-Allow-Origin", main_origin,
+                                false);
+    }
+  }
+
+  bool VerifyRequest(CefRefPtr<CefRequest> request) const override {
+    // Verify that the "Origin" header contains the expected value.
+    const std::string& origin = request->GetHeaderByName("Origin");
+    if (is_cross_origin) {
+      EXPECT_STREQ(main_origin.c_str(), origin.c_str());
+      return main_origin == origin;
+    }
+    EXPECT_TRUE(origin.empty());
+    return origin.empty();
+  }
+};
+
+enum class ExecMode {
+  XHR,
+  FETCH,
+};
+
+std::string GetXhrExecJS(const std::string& sub_url) {
+  return "xhr = new XMLHttpRequest();\n"
+         "xhr.open(\"GET\", \"" +
+         sub_url +
+         "\", true)\n;"
+         "xhr.onload = function(e) {\n"
+         "  if (xhr.readyState === 4) {\n"
+         "    if (xhr.status === 200) {\n"
+         "      onResult(xhr.responseText);\n"
+         "    } else {\n"
+         "      console.log('XMLHttpRequest failed with status ' + "
+         "xhr.status);\n"
+         "      onResult('FAILURE');\n"
+         "    }\n"
+         "  }\n"
+         "};\n"
+         "xhr.onerror = function(e) {\n"
+         "  onResult('FAILURE');\n"
+         "};\n"
+         "xhr.send();\n";
+}
+
+std::string GetFetchExecJS(const std::string& sub_url) {
+  return "fetch('" + sub_url +
+         "')\n"
+         ".then(function(response) {\n"
+         "  if (response.status === 200) {\n"
+         "      response.text().then(function(text) {\n"
+         "          onResult(text);\n"
+         "      }).catch(function(e) {\n"
+         "          onResult('FAILURE')\n;        "
+         "      })\n;"
+         "  } else {\n"
+         "      onResult('FAILURE');\n"
+         "  }\n"
+         "}).catch(function(e) {\n"
+         "  onResult('FAILURE');\n"
+         "});\n";
+}
+
+std::string GetExecMainHtml(ExecMode mode, const std::string& sub_url) {
+  return std::string() +
+         "<html><head>\n"
+         "<script language=\"JavaScript\">\n" +
+         "function onResult(val) {\n"
+         "  if (val === '" +
+         kDefaultText + "') {" + GetSuccessMsgJS() + "} else {" +
+         GetFailureMsgJS() +
+         "}\n}\n"
+         "function execRequest() {\n" +
+         (mode == ExecMode::XHR ? GetXhrExecJS(sub_url)
+                                : GetFetchExecJS(sub_url)) +
+         "}\n</script>\n"
+         "</head><body onload=\"execRequest();\">"
+         "Running execRequest..."
+         "</body></html>";
+}
+
+// XHR and fetch requests behave the same, except for console message contents.
+void SetupExecRequest(ExecMode mode,
+                      TestSetup* setup,
+                      const std::string& test_name,
+                      HandlerType main_handler,
+                      Resource* main_resource,
+                      HandlerType sub_handler,
+                      SubResource* sub_resource,
+                      bool add_header) {
+  const std::string& base_path = "/" + test_name;
+
+  // Expect a single xhr request.
+  sub_resource->Init(sub_handler, base_path + ".sub.txt", kMimeTypeText,
+                     kDefaultText);
+  sub_resource->InitCors(main_handler, add_header);
+
+  // Expect a single main frame request.
+  const std::string& sub_url = sub_resource->GetPathURL();
+  main_resource->Init(main_handler, base_path, kMimeTypeHtml,
+                      GetExecMainHtml(mode, sub_url));
+
+  if (sub_resource->is_cross_origin &&
+      (!sub_resource->supports_cors || !add_header)) {
+    // Expect the cross-origin XHR to be blocked.
+    main_resource->expected_failure_query_ct = 1;
+
+    if (sub_resource->supports_cors && !add_header) {
+      // The request supports CORS, but we didn't add the header.
+      if (mode == ExecMode::XHR) {
+        setup->AddConsoleMessage(
+            "Access to XMLHttpRequest at '" + sub_url + "' from origin '" +
+            sub_resource->main_origin +
+            "' has been blocked by CORS policy: No "
+            "'Access-Control-Allow-Origin' "
+            "header is present on the requested resource.");
+      } else {
+        setup->AddConsoleMessage(
+            "Access to fetch at '" + sub_url + "' from origin '" +
+            sub_resource->main_origin +
+            "' has been blocked by CORS policy: No "
+            "'Access-Control-Allow-Origin' header is present on the requested "
+            "resource. If an opaque response serves your needs, set the "
+            "request's mode to 'no-cors' to fetch the resource with CORS "
+            "disabled.");
+      }
+    } else if (mode == ExecMode::XHR) {
+      setup->AddConsoleMessage(
+          "Access to XMLHttpRequest at '" + sub_url + "' from origin '" +
+          sub_resource->main_origin +
+          "' has been blocked by CORS policy: Cross origin requests are only "
+          "supported for protocol schemes:");
+    } else {
+      setup->AddConsoleMessage(
+          "Fetch API cannot load " + sub_url +
+          ". URL scheme must be \"http\" or \"https\" for CORS request.");
+    }
+  } else {
+    // Expect the (possibly cross-origin) XHR to be allowed.
+    main_resource->expected_success_query_ct = 1;
+  }
+
+  setup->AddResource(main_resource);
+  setup->AddResource(sub_resource);
+}
+
+}  // namespace
+
+// Test XHR requests with different origin combinations.
+#define CORS_TEST_XHR(test_name, handler_main, handler_sub, add_header)    \
+  TEST(CorsTest, Xhr##test_name) {                                         \
+    TestSetup setup;                                                       \
+    Resource resource_main;                                                \
+    SubResource resource_sub;                                              \
+    SetupExecRequest(ExecMode::XHR, &setup, "CorsTest.Xhr" #test_name,     \
+                     HandlerType::handler_main, &resource_main,            \
+                     HandlerType::handler_sub, &resource_sub, add_header); \
+    CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);      \
+    handler->ExecuteTest();                                                \
+    ReleaseAndWaitForDestructor(handler);                                  \
+  }
+
+// Test all origin combinations (same and cross-origin).
+#define CORS_TEST_XHR_ALL(name, add_header)                                    \
+  CORS_TEST_XHR(name##ServerToServer, SERVER, SERVER, add_header)              \
+  CORS_TEST_XHR(name##ServerToHttpScheme, SERVER, HTTP_SCHEME, add_header)     \
+  CORS_TEST_XHR(name##ServerToCustomStandardScheme, SERVER,                    \
+                CUSTOM_STANDARD_SCHEME, add_header)                            \
+  CORS_TEST_XHR(name##ServerToCustomNonStandardScheme, SERVER,                 \
+                CUSTOM_NONSTANDARD_SCHEME, add_header)                         \
+  CORS_TEST_XHR(name##HttpSchemeToServer, HTTP_SCHEME, SERVER, add_header)     \
+  CORS_TEST_XHR(name##HttpSchemeToHttpScheme, HTTP_SCHEME, HTTP_SCHEME,        \
+                add_header)                                                    \
+  CORS_TEST_XHR(name##HttpSchemeToCustomStandardScheme, HTTP_SCHEME,           \
+                CUSTOM_STANDARD_SCHEME, add_header)                            \
+  CORS_TEST_XHR(name##HttpSchemeToCustomNonStandardScheme, HTTP_SCHEME,        \
+                CUSTOM_NONSTANDARD_SCHEME, add_header)                         \
+  CORS_TEST_XHR(name##CustomStandardSchemeToServer, CUSTOM_STANDARD_SCHEME,    \
+                SERVER, add_header)                                            \
+  CORS_TEST_XHR(name##CustomStandardSchemeToHttpScheme,                        \
+                CUSTOM_STANDARD_SCHEME, HTTP_SCHEME, add_header)               \
+  CORS_TEST_XHR(name##CustomStandardSchemeToCustomStandardScheme,              \
+                CUSTOM_STANDARD_SCHEME, CUSTOM_STANDARD_SCHEME, add_header)    \
+  CORS_TEST_XHR(name##CustomStandardSchemeToCustomNonStandardScheme,           \
+                CUSTOM_STANDARD_SCHEME, CUSTOM_NONSTANDARD_SCHEME, add_header) \
+  CORS_TEST_XHR(name##CustomNonStandardSchemeToServer,                         \
+                CUSTOM_NONSTANDARD_SCHEME, SERVER, add_header)                 \
+  CORS_TEST_XHR(name##CustomNonStandardSchemeToHttpScheme,                     \
+                CUSTOM_NONSTANDARD_SCHEME, HTTP_SCHEME, add_header)            \
+  CORS_TEST_XHR(name##CustomNonStandardSchemeToCustomStandardScheme,           \
+                CUSTOM_NONSTANDARD_SCHEME, CUSTOM_STANDARD_SCHEME, add_header) \
+  CORS_TEST_XHR(name##CustomNonStandardSchemeToCustomNonStandardScheme,        \
+                CUSTOM_NONSTANDARD_SCHEME, CUSTOM_NONSTANDARD_SCHEME,          \
+                add_header)
+
+// XHR requests without the "Access-Control-Allow-Origin" header.
+CORS_TEST_XHR_ALL(NoHeader, false)
+
+// XHR requests with the "Access-Control-Allow-Origin" header.
+CORS_TEST_XHR_ALL(WithHeader, true)
+
+// Test fetch requests with different origin combinations.
+#define CORS_TEST_FETCH(test_name, handler_main, handler_sub, add_header)  \
+  TEST(CorsTest, Fetch##test_name) {                                       \
+    TestSetup setup;                                                       \
+    Resource resource_main;                                                \
+    SubResource resource_sub;                                              \
+    SetupExecRequest(ExecMode::FETCH, &setup, "CorsTest.Fetch" #test_name, \
+                     HandlerType::handler_main, &resource_main,            \
+                     HandlerType::handler_sub, &resource_sub, add_header); \
+    CefRefPtr<CorsTestHandler> handler = new CorsTestHandler(&setup);      \
+    handler->ExecuteTest();                                                \
+    ReleaseAndWaitForDestructor(handler);                                  \
+  }
+
+// Test all origin combinations (same and cross-origin).
+#define CORS_TEST_FETCH_ALL(name, add_header)                                 \
+  CORS_TEST_FETCH(name##ServerToServer, SERVER, SERVER, add_header)           \
+  CORS_TEST_FETCH(name##ServerToHttpScheme, SERVER, HTTP_SCHEME, add_header)  \
+  CORS_TEST_FETCH(name##ServerToCustomStandardScheme, SERVER,                 \
+                  CUSTOM_STANDARD_SCHEME, add_header)                         \
+  CORS_TEST_FETCH(name##ServerToCustomNonStandardScheme, SERVER,              \
+                  CUSTOM_NONSTANDARD_SCHEME, add_header)                      \
+  CORS_TEST_FETCH(name##HttpSchemeToServer, HTTP_SCHEME, SERVER, add_header)  \
+  CORS_TEST_FETCH(name##HttpSchemeToHttpScheme, HTTP_SCHEME, HTTP_SCHEME,     \
+                  add_header)                                                 \
+  CORS_TEST_FETCH(name##HttpSchemeToCustomStandardScheme, HTTP_SCHEME,        \
+                  CUSTOM_STANDARD_SCHEME, add_header)                         \
+  CORS_TEST_FETCH(name##HttpSchemeToCustomNonStandardScheme, HTTP_SCHEME,     \
+                  CUSTOM_NONSTANDARD_SCHEME, add_header)                      \
+  CORS_TEST_FETCH(name##CustomStandardSchemeToServer, CUSTOM_STANDARD_SCHEME, \
+                  SERVER, add_header)                                         \
+  CORS_TEST_FETCH(name##CustomStandardSchemeToHttpScheme,                     \
+                  CUSTOM_STANDARD_SCHEME, HTTP_SCHEME, add_header)            \
+  CORS_TEST_FETCH(name##CustomStandardSchemeToCustomStandardScheme,           \
+                  CUSTOM_STANDARD_SCHEME, CUSTOM_STANDARD_SCHEME, add_header) \
+  CORS_TEST_FETCH(name##CustomStandardSchemeToCustomNonStandardScheme,        \
+                  CUSTOM_STANDARD_SCHEME, CUSTOM_NONSTANDARD_SCHEME,          \
+                  add_header)                                                 \
+  CORS_TEST_FETCH(name##CustomNonStandardSchemeToServer,                      \
+                  CUSTOM_NONSTANDARD_SCHEME, SERVER, add_header)              \
+  CORS_TEST_FETCH(name##CustomNonStandardSchemeToHttpScheme,                  \
+                  CUSTOM_NONSTANDARD_SCHEME, HTTP_SCHEME, add_header)         \
+  CORS_TEST_FETCH(name##CustomNonStandardSchemeToCustomStandardScheme,        \
+                  CUSTOM_NONSTANDARD_SCHEME, CUSTOM_STANDARD_SCHEME,          \
+                  add_header)                                                 \
+  CORS_TEST_FETCH(name##CustomNonStandardSchemeToCustomNonStandardScheme,     \
+                  CUSTOM_NONSTANDARD_SCHEME, CUSTOM_NONSTANDARD_SCHEME,       \
+                  add_header)
+
+// Fetch requests without the "Access-Control-Allow-Origin" header.
+CORS_TEST_FETCH_ALL(NoHeader, false)
+
+// Fetch requests with the "Access-Control-Allow-Origin" header.
+CORS_TEST_FETCH_ALL(WithHeader, true)
diff --git a/tests/ceftests/scheme_handler_unittest.cc b/tests/ceftests/scheme_handler_unittest.cc
index 4fd4d076c..ef899c34a 100644
--- a/tests/ceftests/scheme_handler_unittest.cc
+++ b/tests/ceftests/scheme_handler_unittest.cc
@@ -3,6 +3,7 @@
 // can be found in the LICENSE file.
 
 #include <algorithm>
+#include <vector>
 
 #include "include/base/cef_bind.h"
 #include "include/cef_callback.h"
@@ -32,6 +33,7 @@ class TestResults {
     sub_allow_origin.clear();
     exit_url.clear();
     accept_language.clear();
+    console_messages.clear();
     delay = 0;
     got_request.reset();
     got_read.reset();
@@ -69,6 +71,9 @@ class TestResults {
   // Used for testing per-browser Accept-Language.
   std::string accept_language;
 
+  // Used for testing received console messages.
+  std::vector<std::string> console_messages;
+
   // Delay for returning scheme handler results.
   int delay;
 
@@ -104,7 +109,13 @@ class TestSchemeHandler : public TestHandler {
 
   // Necessary to make the method public in order to destroy the test from
   // ClientSchemeHandler::ProcessRequest().
-  void DestroyTest() override { TestHandler::DestroyTest(); }
+  void DestroyTest() override {
+    EXPECT_TRUE(test_results_->console_messages.empty())
+        << "Did not receive expected console message: "
+        << test_results_->console_messages.front();
+
+    TestHandler::DestroyTest();
+  }
 
   void DestroyTestIfDone() {
     if (!test_results_->exit_url.empty() && !test_results_->got_exit_request) {
@@ -206,6 +217,31 @@ class TestSchemeHandler : public TestHandler {
     DestroyTestIfDone();
   }
 
+  bool OnConsoleMessage(CefRefPtr<CefBrowser> browser,
+                        cef_log_severity_t level,
+                        const CefString& message,
+                        const CefString& source,
+                        int line) override {
+    bool expected = false;
+    if (!test_results_->console_messages.empty()) {
+      std::vector<std::string>::iterator it =
+          test_results_->console_messages.begin();
+      for (; it != test_results_->console_messages.end(); ++it) {
+        const std::string& possible = *it;
+        const std::string& actual = message.ToString();
+        if (actual.find(possible) == 0U) {
+          expected = true;
+          test_results_->console_messages.erase(it);
+          break;
+        }
+      }
+    }
+
+    EXPECT_TRUE(expected) << "Unexpected console message: "
+                          << message.ToString();
+    return false;
+  }
+
  protected:
   TestResults* test_results_;
 
@@ -635,6 +671,11 @@ void SetUpXHR(const XHRTestSettings& settings) {
   g_TestResults.sub_allow_origin = settings.sub_allow_origin;
   g_TestResults.sub_redirect_url = settings.sub_redirect_url;
 
+  if (settings.synchronous) {
+    g_TestResults.console_messages.push_back(
+        "Synchronous XMLHttpRequest on the main thread is deprecated");
+  }
+
   std::string request_url;
   if (!settings.sub_redirect_url.empty())
     request_url = settings.sub_redirect_url;
@@ -677,7 +718,6 @@ void SetUpXHR(const XHRTestSettings& settings) {
           "  }"
           "};"
           "xhr.onerror = function(e) {"
-          "  console.log('XMLHttpRequest failed with error ' + e);"
           "  onResult('FAILURE');"
           "};"
           "xhr.send()";
@@ -728,16 +768,12 @@ void SetUpFetch(const FetchTestSettings& settings) {
         "      response.text().then(function(text) {"
         "          onResult(text);"
         "      }).catch(function(e) {"
-        "          console.log('FetchHttpRequest failed with error ' + e);"
         "          onResult('FAILURE');        "
         "      });"
         "  } else {"
-        "      console.log('XMLHttpRequest failed with status ' + "
-        "      response.status);"
         "      onResult('FAILURE');"
         "  }"
         "}).catch(function(e) {"
-        "  console.log('FetchHttpRequest failed with error ' + e);"
         "  onResult('FAILURE');"
         "});"
      << "}"
@@ -1154,6 +1190,11 @@ TEST(SchemeHandlerTest, CustomNonStandardXHRSameOriginSync) {
   settings.sub_url = "customnonstd:xhr%20value";
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'customnonstd:xhr%20value' from origin "
+      "'null' has been blocked by CORS policy: Cross origin requests are only "
+      "supported for protocol schemes:");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1179,6 +1220,11 @@ TEST(SchemeHandlerTest, CustomNonStandardXHRSameOriginAsync) {
   settings.synchronous = false;
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'customnonstd:xhr%20value' from origin "
+      "'null' has been blocked by CORS policy: Cross origin requests are only "
+      "supported for protocol schemes:");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1203,6 +1249,10 @@ TEST(SchemeHandlerTest, CustomStandardFetchSameOrigin) {
   settings.sub_url = "customstd://test/fetch.html";
   SetUpFetch(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Fetch API cannot load customstd://test/fetch.html. URL scheme "
+      "\"customstd\" is not supported.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1251,6 +1301,10 @@ TEST(SchemeHandlerTest, CustomNonStandardFetchSameOrigin) {
   settings.sub_url = "customnonstd:xhr%20value";
   SetUpFetch(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Fetch API cannot load customnonstd:xhr%20value. URL scheme must be "
+      "\"http\" or \"https\" for CORS request.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1290,6 +1344,10 @@ TEST(SchemeHandlerTest, CustomNonStandardXSSSameOrigin) {
   RegisterTestScheme("customnonstd", std::string());
   SetUpXSS("customnonstd:some%20value", "customnonstd:xhr%20value");
 
+  g_TestResults.console_messages.push_back(
+      "Error: Blocked a frame with origin \"null\" from accessing a "
+      "cross-origin frame.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1315,6 +1373,12 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginSync) {
   settings.sub_url = "customstd://test2/xhr.html";
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'customstd://test2/xhr.html' from origin "
+      "'customstd://test1' has been blocked by CORS policy: No "
+      "'Access-Control-Allow-Origin' header is present on the requested "
+      "resource.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1323,7 +1387,11 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginSync) {
   EXPECT_TRUE(g_TestResults.got_read);
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -1341,6 +1409,12 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginAsync) {
   settings.synchronous = false;
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'customstd://test2/xhr.html' from origin "
+      "'customstd://test1' has been blocked by CORS policy: No "
+      "'Access-Control-Allow-Origin' header is present on the requested "
+      "resource.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1349,7 +1423,11 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginAsync) {
   EXPECT_TRUE(g_TestResults.got_read);
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -1366,6 +1444,13 @@ TEST(SchemeHandlerTest, CustomStandardFetchDifferentOrigin) {
   settings.sub_url = "customstdfetch://test2/fetch.html";
   SetUpFetch(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to fetch at 'customstdfetch://test2/fetch.html' from origin "
+      "'customstdfetch://test1' has been blocked by CORS policy: No "
+      "'Access-Control-Allow-Origin' header is present on the requested "
+      "resource. If an opaque response serves your needs, set the request's "
+      "mode to 'no-cors' to fetch the resource with CORS disabled.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1374,7 +1459,11 @@ TEST(SchemeHandlerTest, CustomStandardFetchDifferentOrigin) {
   EXPECT_TRUE(g_TestResults.got_read);
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -1387,6 +1476,10 @@ TEST(SchemeHandlerTest, CustomStandardXSSDifferentOrigin) {
   RegisterTestScheme("customstd", "test2");
   SetUpXSS("customstd://test1/run.html", "customstd://test2/iframe.html");
 
+  g_TestResults.console_messages.push_back(
+      "Error: Blocked a frame with origin \"customstd://test2\" from accessing "
+      "a cross-origin frame.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1408,6 +1501,10 @@ TEST(SchemeHandlerTest, CustomStandardXSSDifferentProtocolHttp) {
   RegisterTestScheme("http", "test2");
   SetUpXSS("customstd://test1/run.html", "http://test2/iframe.html");
 
+  g_TestResults.console_messages.push_back(
+      "Error: Blocked a frame with origin \"http://test2\" from accessing a "
+      "cross-origin frame.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1430,6 +1527,10 @@ TEST(SchemeHandlerTest, CustomStandardXSSDifferentProtocolCustomNonStandard) {
   RegisterTestScheme("customnonstd", std::string());
   SetUpXSS("customstd://test1/run.html", "customnonstd:some%20value");
 
+  g_TestResults.console_messages.push_back(
+      "Error: Blocked a frame with origin \"null\" from accessing a "
+      "cross-origin frame.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1451,6 +1552,10 @@ TEST(SchemeHandlerTest, HttpXSSDifferentProtocolCustomStandard) {
   RegisterTestScheme("customstd", "test2");
   SetUpXSS("http://test1/run.html", "customstd://test2/iframe.html");
 
+  g_TestResults.console_messages.push_back(
+      "Error: Blocked a frame with origin \"customstd://test2\" from accessing "
+      "a cross-origin frame.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1472,6 +1577,10 @@ TEST(SchemeHandlerTest, HttpXSSDifferentProtocolCustomNonStandard) {
   RegisterTestScheme("customnonstd", std::string());
   SetUpXSS("http://test1/run.html", "customnonstd:some%20value");
 
+  g_TestResults.console_messages.push_back(
+      "Error: Blocked a frame with origin \"null\" from accessing a "
+      "cross-origin frame.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1497,6 +1606,12 @@ TEST(SchemeHandlerTest, HttpXHRDifferentOriginSync) {
   settings.sub_url = "http://test2/xhr.html";
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'http://test2/xhr.html' from origin "
+      "'http://test1' has been blocked by CORS policy: No "
+      "'Access-Control-Allow-Origin' header is present on the requested "
+      "resource.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1505,7 +1620,11 @@ TEST(SchemeHandlerTest, HttpXHRDifferentOriginSync) {
   EXPECT_TRUE(g_TestResults.got_read);
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -1523,6 +1642,12 @@ TEST(SchemeHandlerTest, HttpXHRDifferentOriginAsync) {
   settings.synchronous = false;
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'http://test2/xhr.html' from origin "
+      "'http://test1' has been blocked by CORS policy: No "
+      "'Access-Control-Allow-Origin' header is present on the requested "
+      "resource.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1531,7 +1656,11 @@ TEST(SchemeHandlerTest, HttpXHRDifferentOriginAsync) {
   EXPECT_TRUE(g_TestResults.got_read);
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -1548,6 +1677,13 @@ TEST(SchemeHandlerTest, HttpFetchDifferentOriginAsync) {
   settings.sub_url = "http://test2/fetch.html";
   SetUpFetch(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to fetch at 'http://test2/fetch.html' from origin 'http://test1' "
+      "has been blocked by CORS policy: No 'Access-Control-Allow-Origin' "
+      "header is present on the requested resource. If an opaque response "
+      "serves your needs, set the request's mode to 'no-cors' to fetch the "
+      "resource with CORS disabled.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -1556,7 +1692,11 @@ TEST(SchemeHandlerTest, HttpFetchDifferentOriginAsync) {
   EXPECT_TRUE(g_TestResults.got_read);
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -1569,6 +1709,10 @@ TEST(SchemeHandlerTest, HttpXSSDifferentOrigin) {
   RegisterTestScheme("http", "test2");
   SetUpXSS("http://test1/run.html", "http://test2/xss.html");
 
+  g_TestResults.console_messages.push_back(
+      "Error: Blocked a frame with origin \"http://test2\" from accessing a "
+      "cross-origin frame.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -2085,6 +2229,12 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginRedirectSync) {
   settings.sub_redirect_url = "customstd://test1/xhr.html";
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'customstd://test2/xhr.html' (redirected "
+      "from 'customstd://test1/xhr.html') from origin 'customstd://test1' has "
+      "been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is "
+      "present on the requested resource.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -2094,7 +2244,11 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginRedirectSync) {
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_redirect);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -2113,6 +2267,12 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginRedirectAsync) {
   settings.synchronous = false;
   SetUpXHR(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to XMLHttpRequest at 'customstd://test2/xhr.html' (redirected "
+      "from 'customstd://test1/xhr.html') from origin 'customstd://test1' has "
+      "been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is "
+      "present on the requested resource.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -2122,7 +2282,11 @@ TEST(SchemeHandlerTest, CustomStandardXHRDifferentOriginRedirectAsync) {
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_redirect);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -2140,6 +2304,14 @@ TEST(SchemeHandlerTest, CustomStandardFetchDifferentOriginRedirect) {
   settings.sub_redirect_url = "customstdfetch://test1/fetch.html";
   SetUpFetch(settings);
 
+  g_TestResults.console_messages.push_back(
+      "Access to fetch at 'customstdfetch://test2/fetch.html' (redirected from "
+      "'customstdfetch://test1/fetch.html') from origin "
+      "'customstdfetch://test1' has been blocked by CORS policy: No "
+      "'Access-Control-Allow-Origin' header is present on the requested "
+      "resource. If an opaque response serves your needs, set the request's "
+      "mode to 'no-cors' to fetch the resource with CORS disabled.");
+
   CefRefPtr<TestSchemeHandler> handler = new TestSchemeHandler(&g_TestResults);
   handler->ExecuteTest();
   ReleaseAndWaitForDestructor(handler);
@@ -2149,7 +2321,11 @@ TEST(SchemeHandlerTest, CustomStandardFetchDifferentOriginRedirect) {
   EXPECT_TRUE(g_TestResults.got_output);
   EXPECT_TRUE(g_TestResults.got_sub_redirect);
   EXPECT_TRUE(g_TestResults.got_sub_request);
-  EXPECT_TRUE(g_TestResults.got_sub_read);
+  if (!IsOutOfBlinkCorsEnabled()) {
+    EXPECT_TRUE(g_TestResults.got_sub_read);
+  } else {
+    EXPECT_FALSE(g_TestResults.got_sub_read);
+  }
   EXPECT_FALSE(g_TestResults.got_sub_success);
 
   ClearTestSchemes();
@@ -2429,6 +2605,7 @@ void RegisterSchemeHandlerCustomSchemes(
   // Add a custom standard scheme.
   registrar->AddCustomScheme(
       "customstd", CEF_SCHEME_OPTION_STANDARD | CEF_SCHEME_OPTION_CORS_ENABLED);
+  // Also used in cors_unittest.cc.
   registrar->AddCustomScheme("customstdfetch",
                              CEF_SCHEME_OPTION_STANDARD |
                                  CEF_SCHEME_OPTION_CORS_ENABLED |
diff --git a/tests/ceftests/test_handler.cc b/tests/ceftests/test_handler.cc
index ff064bf72..e20b86e50 100644
--- a/tests/ceftests/test_handler.cc
+++ b/tests/ceftests/test_handler.cc
@@ -10,6 +10,7 @@
 #include "include/cef_stream.h"
 #include "include/wrapper/cef_closure_task.h"
 #include "include/wrapper/cef_stream_resource_handler.h"
+#include "tests/ceftests/test_request.h"
 #include "tests/shared/common/client_switches.h"
 
 #if defined(USE_AURA)
@@ -261,15 +262,8 @@ CefRefPtr<CefResourceHandler> TestHandler::GetResourceHandler(
   EXPECT_IO_THREAD();
 
   if (resource_map_.size() > 0) {
-    CefString url = request->GetURL();
-
-    // Ignore the query component, if any.
-    std::string urlStr = url;
-    size_t idx = urlStr.find('?');
-    if (idx > 0)
-      urlStr = urlStr.substr(0, idx);
-
-    ResourceMap::const_iterator it = resource_map_.find(urlStr);
+    const std::string& url = test_request::GetPathURL(request->GetURL());
+    ResourceMap::const_iterator it = resource_map_.find(url);
     if (it != resource_map_.end()) {
       // Return the previously mapped resource
       CefRefPtr<CefStreamReader> stream = CefStreamReader::CreateForData(
diff --git a/tests/ceftests/test_request.cc b/tests/ceftests/test_request.cc
index 8de702c82..216e6290d 100644
--- a/tests/ceftests/test_request.cc
+++ b/tests/ceftests/test_request.cc
@@ -4,9 +4,13 @@
 
 #include "tests/ceftests/test_request.h"
 
+#include <algorithm>
+
+#include "include/cef_stream.h"
 #include "include/cef_urlrequest.h"
 #include "include/wrapper/cef_closure_task.h"
 #include "include/wrapper/cef_helpers.h"
+#include "include/wrapper/cef_stream_resource_handler.h"
 
 namespace test_request {
 
@@ -106,4 +110,39 @@ void Send(const SendConfig& config, const RequestDoneCallback& callback) {
   }
 }
 
+std::string GetPathURL(const std::string& url) {
+  const size_t index1 = url.find('?');
+  const size_t index2 = url.find('#');
+  size_t index = -1;
+  if (index1 >= 0 && index2 >= 0) {
+    index = std::min(index1, index2);
+  } else if (index1 >= 0) {
+    index = index1;
+  } else if (index2 >= 0) {
+    index = index2;
+  }
+  if (index >= 0) {
+    return url.substr(0, index);
+  }
+  return url;
+}
+
+CefRefPtr<CefResourceHandler> CreateResourceHandler(
+    CefRefPtr<CefResponse> response,
+    const std::string& response_data) {
+  CefRefPtr<CefStreamReader> stream;
+  if (!response_data.empty()) {
+    stream = CefStreamReader::CreateForData(
+        static_cast<void*>(const_cast<char*>(response_data.c_str())),
+        response_data.length());
+  }
+
+  CefResponse::HeaderMap headerMap;
+  response->GetHeaderMap(headerMap);
+
+  return new CefStreamResourceHandler(
+      response->GetStatus(), response->GetStatusText(), response->GetMimeType(),
+      headerMap, stream);
+}
+
 }  // namespace test_request
diff --git a/tests/ceftests/test_request.h b/tests/ceftests/test_request.h
index 7aa6b7475..34ca17fd3 100644
--- a/tests/ceftests/test_request.h
+++ b/tests/ceftests/test_request.h
@@ -12,6 +12,7 @@
 #include "include/cef_frame.h"
 #include "include/cef_request.h"
 #include "include/cef_request_context.h"
+#include "include/cef_resource_handler.h"
 #include "include/cef_response.h"
 
 namespace test_request {
@@ -64,6 +65,14 @@ struct SendConfig {
 // request completes.
 void Send(const SendConfig& config, const RequestDoneCallback& callback);
 
+// Removes query and/or fragment components from |url|.
+std::string GetPathURL(const std::string& url);
+
+// Creates a new resource handler that returns the specified response.
+CefRefPtr<CefResourceHandler> CreateResourceHandler(
+    CefRefPtr<CefResponse> response,
+    const std::string& response_data);
+
 }  // namespace test_request
 
 #endif  // CEF_TESTS_CEFTESTS_TEST_REQUEST_H_
diff --git a/tests/ceftests/test_server.cc b/tests/ceftests/test_server.cc
index 5075a0a24..a907d3b75 100644
--- a/tests/ceftests/test_server.cc
+++ b/tests/ceftests/test_server.cc
@@ -447,6 +447,27 @@ CefRefPtr<CefRegistration> AddObserverAndStart(
   return AddObserver(observer, base::Bind(Start, callback));
 }
 
+void SendResponse(CefRefPtr<CefServer> server,
+                  int connection_id,
+                  CefRefPtr<CefResponse> response,
+                  const std::string& response_data) {
+  const int response_code = response->GetStatus();
+  const CefString& content_type = response->GetMimeType();
+  int64 content_length = static_cast<int64>(response_data.size());
+
+  CefResponse::HeaderMap extra_headers;
+  response->GetHeaderMap(extra_headers);
+
+  server->SendHttpResponse(connection_id, response_code, content_type,
+                           content_length, extra_headers);
+
+  if (content_length != 0) {
+    server->SendRawData(connection_id, response_data.data(),
+                        response_data.size());
+    server->CloseConnection(connection_id);
+  }
+}
+
 // ObserverHelper
 
 ObserverHelper::ObserverHelper() : weak_ptr_factory_(this) {
diff --git a/tests/ceftests/test_server.h b/tests/ceftests/test_server.h
index 958394de5..00d39e3f2 100644
--- a/tests/ceftests/test_server.h
+++ b/tests/ceftests/test_server.h
@@ -11,6 +11,7 @@
 #include "include/base/cef_bind.h"
 #include "include/cef_registration.h"
 #include "include/cef_request.h"
+#include "include/cef_response.h"
 #include "include/cef_server.h"
 
 namespace test_server {
@@ -76,6 +77,12 @@ CefRefPtr<CefRegistration> AddObserverAndStart(
     Observer* observer,
     const StartDoneCallback& callback);
 
+// Helper for sending a fully qualified response.
+void SendResponse(CefRefPtr<CefServer> server,
+                  int connection_id,
+                  CefRefPtr<CefResponse> response,
+                  const std::string& response_data);
+
 // Helper for managing Observer registration and callbacks. Only used on the UI
 // thread.
 class ObserverHelper : Observer {
diff --git a/tests/ceftests/test_util.cc b/tests/ceftests/test_util.cc
index 5058b1f60..723c03208 100644
--- a/tests/ceftests/test_util.cc
+++ b/tests/ceftests/test_util.cc
@@ -281,6 +281,17 @@ bool TestOldResourceAPI() {
   return state ? true : false;
 }
 
+bool IsOutOfBlinkCorsEnabled() {
+  static int state = -1;
+  if (state == -1) {
+    CefRefPtr<CefCommandLine> command_line =
+        CefCommandLine::GetGlobalCommandLine();
+    const std::string& value = command_line->GetSwitchValue("disable-features");
+    state = value.find("OutOfBlinkCors") == std::string::npos ? 1 : 0;
+  }
+  return state ? true : false;
+}
+
 CefRefPtr<CefRequestContext> CreateTestRequestContext(
     TestRequestContextMode mode,
     const std::string& cache_path) {
diff --git a/tests/ceftests/test_util.h b/tests/ceftests/test_util.h
index 8bacbc4a8..d45f10e42 100644
--- a/tests/ceftests/test_util.h
+++ b/tests/ceftests/test_util.h
@@ -81,6 +81,9 @@ inline bool IsTestRequestContextModeCustom(TestRequestContextMode mode) {
 // Returns true if the old CefResourceHandler API should be tested.
 bool TestOldResourceAPI();
 
+// Returns true if OutOfBlinkCors is enabled.
+bool IsOutOfBlinkCorsEnabled();
+
 // Return a RequestContext object matching the specified |mode|.
 // |cache_path| may be specified for CUSTOM modes.
 // Use the RC_TEST_GROUP_BASE macro to test all valid combinations.