From f24f885eeb7fe358a41e5544e29d76f74210c787 Mon Sep 17 00:00:00 2001
From: Marshall Greenblatt <magreenblatt@gmail.com>
Date: Fri, 4 May 2018 16:42:02 +0200
Subject: [PATCH] Fix DCHECK due to unreliable is_main_frame state on XHR
 requests (issue #2433)

---
 libcef/browser/browser_host_impl.cc | 15 +++++++++------
 libcef/browser/browser_host_impl.h  |  6 +++---
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/libcef/browser/browser_host_impl.cc b/libcef/browser/browser_host_impl.cc
index d65a78ada..320dd2438 100644
--- a/libcef/browser/browser_host_impl.cc
+++ b/libcef/browser/browser_host_impl.cc
@@ -1590,10 +1590,13 @@ CefRefPtr<CefFrame> CefBrowserHostImpl::GetFrameForRequest(
       content::ResourceRequestInfo::ForRequest(request);
   if (!info)
     return nullptr;
-  // The value of |IsMainFrame| is unreliable when |IsDownload| returns true.
+  // The value of |IsMainFrame| is unreliable in these cases.
+  const bool is_main_frame_state_flaky =
+      info->IsDownload() ||
+      info->GetResourceType() == content::RESOURCE_TYPE_XHR;
   return GetOrCreateFrame(info->GetRenderFrameID(), info->GetFrameTreeNodeId(),
                           CefFrameHostImpl::kUnspecifiedFrameId,
-                          info->IsMainFrame(), info->IsDownload(),
+                          info->IsMainFrame(), is_main_frame_state_flaky,
                           base::string16(), GURL());
 }
 
@@ -3224,7 +3227,7 @@ CefRefPtr<CefFrame> CefBrowserHostImpl::GetOrCreateFrame(
     int frame_tree_node_id,
     int64 parent_frame_id,
     bool is_main_frame,
-    bool is_download,
+    bool is_main_frame_state_flaky,
     base::string16 frame_name,
     const GURL& frame_url) {
   // We need either a valid |frame_id| or a valid |frame_tree_node_id|.
@@ -3245,13 +3248,13 @@ CefRefPtr<CefFrame> CefBrowserHostImpl::GetOrCreateFrame(
 
   if (frame_id < 0) {
     // With PlzNavigate the renderer process representation might not exist yet.
-    if ((is_main_frame || is_download) &&
+    if ((is_main_frame || is_main_frame_state_flaky) &&
         main_frame_id_ != CefFrameHostImpl::kInvalidFrameId) {
       // Operating in the main frame. Continue using the existing main frame
       // object until the new renderer process representation is created.
       frame_id = main_frame_id_;
     } else {
-      if (is_main_frame || is_download) {
+      if (is_main_frame || is_main_frame_state_flaky) {
         // Always use the same pending object for the main frame.
         frame_tree_node_id = kMainFrameTreeNodeId;
       }
@@ -3319,7 +3322,7 @@ CefRefPtr<CefFrame> CefBrowserHostImpl::GetOrCreateFrame(
     }
   }
 
-  if (!frame_created && !is_download)
+  if (!frame_created && !is_main_frame_state_flaky)
     frame->SetAttributes(is_main_frame, url, name, parent_frame_id);
 
 #if DCHECK_IS_ON()
diff --git a/libcef/browser/browser_host_impl.h b/libcef/browser/browser_host_impl.h
index d09a082ed..da7e94132 100644
--- a/libcef/browser/browser_host_impl.h
+++ b/libcef/browser/browser_host_impl.h
@@ -586,13 +586,13 @@ class CefBrowserHostImpl : public CefBrowserHost,
   // if PlzNavigate is disabled; or >= 0 otherwise. |parent_frame_id| will be
   // CefFrameHostImpl::kUnspecifiedFrameId if unknown. In cases where |frame_id|
   // is < 0 either the existing main frame object or a pending object will be
-  // returned depending on current state. If |is_download| is true then the
-  // value of |is_main_frame| cannot be relied on.
+  // returned depending on current state. If |is_main_frame_state_flaky| is true
+  // then the value of |is_main_frame| cannot be relied on.
   CefRefPtr<CefFrame> GetOrCreateFrame(int64 frame_id,
                                        int frame_tree_node_id,
                                        int64 parent_frame_id,
                                        bool is_main_frame,
-                                       bool is_download,
+                                       bool is_main_frame_state_flaky,
                                        base::string16 frame_name,
                                        const GURL& frame_url);