Null check content view core before using it.

content/browser/renderer_host/render_widget_host_view_android.cc

 // Copyright (c) 2012 The Chromium 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 "content/browser/renderer_host/render_widget_host_view_android.h"
 
 #include <android/bitmap.h>
 
 #include "base/android/build_info.h"
 #include "base/basictypes.h"
@@ skipping 1098 matching lines @@
   last_frame_info_.reset(new LastFrameInfo(output_surface_id, frame.Pass()));
 }
 
 void RenderWidgetHostViewAndroid::SynchronousFrameMetadata(
     const cc::CompositorFrameMetadata& frame_metadata) {
   // This is a subset of OnSwapCompositorFrame() used in the synchronous
   // compositor flow.
   OnFrameMetadataUpdated(frame_metadata);
   ComputeContentsSize(frame_metadata);
 
+  // Content view core may possibly be destructed at this time.

[boliu, 2014/10/27 22:19:05]

No need for comment

[hush (inactive), 2014/10/27 22:24:03]

Done.

+  if (content_view_core_ == NULL)

[boliu, 2014/10/27 22:19:05]

if (!content_view_core_)

And I think you can put it at the top of the method

[hush (inactive), 2014/10/27 22:24:03]

Done.

+    return;
+
   // DevTools ScreenCast support for Android WebView.
   WebContents* web_contents = content_view_core_->GetWebContents();
   if (DevToolsAgentHost::HasFor(web_contents)) {
     scoped_refptr<DevToolsAgentHost> dtah =
         DevToolsAgentHost::GetOrCreateFor(web_contents);
     // Unblock the compositor.
     BrowserThread::PostTask(
         BrowserThread::UI, FROM_HERE,
         base::Bind(&RenderViewDevToolsAgentHost::SynchronousSwapCompositorFrame,
                    static_cast<RenderViewDevToolsAgentHost*>(dtah.get()),
@@ skipping 665 matching lines @@
   results->orientationAngle = display.RotationAsDegree();
   results->orientationType =
       RenderWidgetHostViewBase::GetOrientationTypeForMobile(display);
   gfx::DeviceDisplayInfo info;
   results->depth = info.GetBitsPerPixel();
   results->depthPerComponent = info.GetBitsPerComponent();
   results->isMonochrome = (results->depthPerComponent == 0);
 }
 
 } // namespace content