Added FrameFuture class

android_webview/browser/render_thread_manager.h

Index: android_webview/browser/render_thread_manager.h
diff --git a/android_webview/browser/render_thread_manager.h b/android_webview/browser/render_thread_manager.h
index b758526d03ad6cd939278437837cd0ac6f039344..067e10faaeef3d2b0c5b8fc02149b68360822703 100644
--- a/android_webview/browser/render_thread_manager.h
+++ b/android_webview/browser/render_thread_manager.h
@@ -48,6 +48,9 @@ class RenderThreadManager : public CompositorFrameConsumer {
       CompositorFrameProducer* compositor_frame_producer) override;
   void SetScrollOffsetOnUI(gfx::Vector2d scroll_offset) override;
   void SetFrameOnUI(std::unique_ptr<ChildFrame> frame) override;
+  void SetFrameFutureOnUI(

[boliu, 2016/09/22 23:05:32]

I think you can just merge this with SetFrameOnUI. Have the synchronous pass in 
null frame_future.

[ojars, 2016/09/28 00:17:59]

Done.

+      const scoped_refptr<content::SynchronousCompositor::FrameFuture>&
+          frame_future) override;
   void InitializeHardwareDrawIfNeededOnUI() override;
   ParentCompositorDrawConstraints GetParentDrawConstraintsOnUI() const override;
   void SwapReturnedResourcesOnUI(
@@ -108,6 +111,8 @@ class RenderThreadManager : public CompositorFrameConsumer {
   bool hardware_renderer_has_frame_;
   gfx::Vector2d scroll_offset_;
   std::unique_ptr<ChildFrame> child_frame_;
+  const bool async_on_draw_hardware_;
+  scoped_refptr<content::SynchronousCompositor::FrameFuture> frame_future_;
   bool inside_hardware_release_;
   ParentCompositorDrawConstraints parent_draw_constraints_;
   ReturnedResourcesMap returned_resources_map_;