Add plugin placeholder and policy support (issue #1708)

- Default plugin loading policy can be specified using the new
  `--plugin-policy=[allow|block|detect]` command-line flag.
- Move CefRequestHandler::OnBeforePluginLoad to
  CefRequestContextHandler and add a new policy argument that
  supports different actions (allow, block, detect, disable) on a
  per-plugin-instance basis.
- Add CefContextMenuHandler::RunContextMenu for providing a custom
  context menu implementation.
- Add CefResourceBundleHandler::GetDataResourceForScale for
  returning scaled resources (issue #1272).
- Add CefResourceBundle for retrieving resources from the resource
  bundle (*.pak) files loaded by CEF during startup or via the
  CefResourceBundleHandler.
- Linux: Fix Debug build IO access warning with CefGetMimeType.
- cef_unittests: Move the refcounting implementation from TestHandler
  to subclasses in order to support interface inheritance from
  subclasses.

libcef/common/cef_messages.h

@@ -163,6 +163,11 @@ IPC_MESSAGE_ROUTED1(CefMsg_Response,
 IPC_MESSAGE_ROUTED1(CefMsg_ResponseAck,
                     int /* request_id */)
 
+// Tells the render frame to load all blocked plugins with the given identifier.
+// Based on ChromeViewMsg_LoadBlockedPlugins.
+IPC_MESSAGE_ROUTED1(CefViewMsg_LoadBlockedPlugins,
+                    std::string /* identifier */)
+
 // Sent on process startup to indicate whether this process is running in
 // incognito mode. Based on ChromeViewMsg_SetIsIncognitoProcess.
 IPC_MESSAGE_CONTROL1(CefProcessMsg_SetIsIncognitoProcess,

libcef/common/cef_switches.cc

@@ -116,4 +116,14 @@ const char kWidevineCdmPath[]             = "widevine-cdm-path";
 // Widevine CDM version.
 const char kWidevineCdmVersion[]          = "widevine-cdm-version";
 
+// Default plugin policy action.
+const char kPluginPolicy[]                = "plugin-policy";
+// Allow the content. This is the default value.
+const char kPluginPolicy_Allow[]          = "allow";
+// Allow important content and block unimportant content based on heuristics.
+// The user can manually load blocked content.
+const char kPluginPolicy_Detect[]         = "detect";
+// Block the content. The user can manually load blocked content.
+const char kPluginPolicy_Block[]          = "block";
+
 }  // namespace switches

libcef/common/cef_switches.h

@@ -48,6 +48,10 @@ extern const char kEnableNPAPI[];
 extern const char kEnableWidevineCdm[];
 extern const char kWidevineCdmPath[];
 extern const char kWidevineCdmVersion[];
+extern const char kPluginPolicy[];
+extern const char kPluginPolicy_Allow[];
+extern const char kPluginPolicy_Detect[];
+extern const char kPluginPolicy_Block[];
 
 }  // namespace switches
 

libcef/common/content_client.cc

@@ -433,8 +433,15 @@ bool CefContentClient::GetRawDataResource(int resource_id,
     if (handler.get()) {
       void* data = NULL;
       size_t data_size = 0;
-      if (handler->GetDataResource(resource_id, data, data_size))
+      if (scale_factor != ui::SCALE_FACTOR_NONE) {
+        if (handler->GetDataResourceForScale(
+              resource_id, static_cast<cef_scale_factor_t>(scale_factor), data,
+              data_size)) {
+          *value = base::StringPiece(static_cast<char*>(data), data_size);
+        }
+      } else if (handler->GetDataResource(resource_id, data, data_size)) {
         *value = base::StringPiece(static_cast<char*>(data), data_size);
+      }
     }
   }
 

libcef/common/main_delegate.cc

@@ -27,10 +27,12 @@
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/widevine_cdm_constants.h"
+#include "components/content_settings/core/common/content_settings_pattern.h"
 #include "content/public/browser/browser_main_runner.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/main_function_params.h"
+#include "extensions/common/constants.h"
 #include "pdf/pdf.h"
 #include "ui/base/layout.h"
 #include "ui/base/resource/resource_bundle.h"
@@ -483,6 +485,9 @@ bool CefMainDelegate::BasicStartupComplete(int* exit_code) {
 
   logging::InitLogging(log_settings);
 
+  ContentSettingsPattern::SetNonWildcardDomainNonPortScheme(
+      extensions::kExtensionScheme);
+
   content::SetContentClient(&content_client_);
 
   return false;

libcef/common/parser_impl.cc

@@ -8,6 +8,7 @@
 #include "libcef/renderer/webkit_glue.h"
 
 #include "base/base64.h"
+#include "base/threading/thread_restrictions.h"
 #include "net/base/escape.h"
 #include "net/base/mime_util.h"
 #include "third_party/WebKit/public/platform/WebString.h"
@@ -76,6 +77,10 @@ bool CefCreateURL(const CefURLParts& parts,
 }
 
 CefString CefGetMimeType(const CefString& extension) {
+  // Requests should not block on the disk!  On POSIX this goes to disk.
+  // http://code.google.com/p/chromium/issues/detail?id=59849
+  base::ThreadRestrictions::ScopedAllowIO allow_io;
+
   std::string mime_type;
   net::GetMimeTypeFromExtension(extension, &mime_type);
   return mime_type;

libcef/common/resource_bundle_impl.cc

@@ -0,0 +1,47 @@
+// Copyright (c) 2015 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 "libcef/common/resource_bundle_impl.h"
+
+#include "ui/base/resource/resource_bundle.h"
+
+CefResourceBundleImpl::CefResourceBundleImpl() {
+}
+
+CefString CefResourceBundleImpl::GetLocalizedString(int string_id) {
+  if (!ui::ResourceBundle::HasSharedInstance())
+    return CefString();
+
+  return ui::ResourceBundle::GetSharedInstance().GetLocalizedString(string_id);
+}
+
+bool CefResourceBundleImpl::GetDataResource(int resource_id,
+                                            void*& data,
+                                            size_t& data_size) {
+  return GetDataResourceForScale(resource_id, SCALE_FACTOR_NONE, data,
+                                 data_size);
+}
+
+bool CefResourceBundleImpl::GetDataResourceForScale(int resource_id,
+                                                    ScaleFactor scale_factor,
+                                                    void*& data,
+                                                    size_t& data_size) {
+  if (!ui::ResourceBundle::HasSharedInstance())
+    return false;
+
+  const base::StringPiece& result =
+      ui::ResourceBundle::GetSharedInstance().GetRawDataResourceForScale(
+          resource_id, static_cast<ui::ScaleFactor>(scale_factor));
+  if (result.empty())
+    return false;
+
+  data = const_cast<char*>(result.data());
+  data_size = result.size();
+  return true;
+}
+
+// static
+CefRefPtr<CefResourceBundle> CefResourceBundle::GetGlobal() {
+  return new CefResourceBundleImpl();
+}

libcef/common/resource_bundle_impl.h

@@ -0,0 +1,31 @@
+// Copyright (c) 2015 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.
+
+#ifndef CEF_LIBCEF_COMMON_RESOURCE_BUNDLE_IMPL_H_
+#define CEF_LIBCEF_COMMON_RESOURCE_BUNDLE_IMPL_H_
+#pragma once
+
+
+#include "include/cef_resource_bundle.h"
+
+class CefResourceBundleImpl : public CefResourceBundle {
+ public:
+  CefResourceBundleImpl();
+
+  // CefResourceBundle methods.
+  CefString GetLocalizedString(int string_id) override;
+  bool GetDataResource(int resource_id,
+                       void*& data,
+                       size_t& data_size) override;
+  bool GetDataResourceForScale(int resource_id,
+                               ScaleFactor scale_factor,
+                               void*& data,
+                               size_t& data_size) override;
+
+ private:
+  IMPLEMENT_REFCOUNTING(CefResourceBundleImpl);
+  DISALLOW_COPY_AND_ASSIGN(CefResourceBundleImpl);
+};
+
+#endif  // CEF_LIBCEF_COMMON_RESOURCE_BUNDLE_IMPL_H_