[Reland] Post loading tasks on the appropriate WebFrameScheduler's queue

content/renderer/renderer_blink_platform_impl.h

Index: content/renderer/renderer_blink_platform_impl.h
diff --git a/content/renderer/renderer_blink_platform_impl.h b/content/renderer/renderer_blink_platform_impl.h
index 6a64c595196f1196d3fe736c140190fed779d4d0..428bae744afeb5fa323c24200479570fc37f4256 100644
--- a/content/renderer/renderer_blink_platform_impl.h
+++ b/content/renderer/renderer_blink_platform_impl.h
@@ -205,6 +205,10 @@ class CONTENT_EXPORT RendererBlinkPlatformImpl : public BlinkPlatformImpl {
     return web_database_observer_impl_.get();
   }
 
+ protected:
+  scoped_refptr<base::SingleThreadTaskRunner>
+  LoadingTaskRunnerForCurrentThread() override;
+
  private:
   bool CheckPreparsedJsCachingEnabled() const;
 
@@ -254,6 +258,7 @@ class CONTENT_EXPORT RendererBlinkPlatformImpl : public BlinkPlatformImpl {
   scoped_ptr<DeviceOrientationEventPump> device_orientation_event_pump_;
 
   scoped_refptr<base::SingleThreadTaskRunner> default_task_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> loading_task_runner_;
   scoped_refptr<IPC::SyncMessageFilter> sync_message_filter_;
   scoped_refptr<ThreadSafeSender> thread_safe_sender_;
   scoped_refptr<QuotaMessageFilter> quota_message_filter_;