Use IDCompositionSurface to implement DirectCompositionSurfaceWin.

content/browser/compositor/gpu_browser_compositor_output_surface.h

Index: content/browser/compositor/gpu_browser_compositor_output_surface.h
diff --git a/content/browser/compositor/gpu_browser_compositor_output_surface.h b/content/browser/compositor/gpu_browser_compositor_output_surface.h
index c250526416deafaf5638e3cbc9b11570757d1d98..f1a764987f0d293d8422ec8ff2436bee6fa20167 100644
--- a/content/browser/compositor/gpu_browser_compositor_output_surface.h
+++ b/content/browser/compositor/gpu_browser_compositor_output_surface.h
@@ -75,12 +75,17 @@ class GpuBrowserCompositorOutputSurface
   bool IsDisplayedAsOverlayPlane() const override;
   unsigned GetOverlayTextureId() const override;
   bool SurfaceIsSuspendForRecycle() const override;
+  void SetDrawRectangle(const gfx::Rect& rect) override;
 
  protected:
   gpu::CommandBufferProxyImpl* GetCommandBufferProxy();
 
   cc::OutputSurfaceClient* client_ = nullptr;
   std::unique_ptr<ReflectorTexture> reflector_texture_;
+  bool set_draw_rectangle_for_frame_ = false;
+  // True if the draw rectangle has been set at all since the last resize.
+  bool has_set_draw_rectangle_ = false;

[sunnyps, 2017/02/14 22:09:13]

nit: has_set_draw_rectangle_since_last_resize_

+  gfx::Size size_;
   base::WeakPtrFactory<GpuBrowserCompositorOutputSurface> weak_ptr_factory_;
 
  private: