Use IDCompositionSurface to implement DirectCompositionSurfaceWin.

content/browser/compositor/gpu_browser_compositor_output_surface.h

 // Copyright 2014 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.
 
 #ifndef CONTENT_BROWSER_COMPOSITOR_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
 #define CONTENT_BROWSER_COMPOSITOR_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 57 matching lines @@
   void Reshape(const gfx::Size& size,
                float device_scale_factor,
                const gfx::ColorSpace& color_space,
                bool has_alpha,
                bool use_stencil) override;
   void SwapBuffers(cc::OutputSurfaceFrame frame) override;
   uint32_t GetFramebufferCopyTextureFormat() override;
   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:
   DISALLOW_COPY_AND_ASSIGN(GpuBrowserCompositorOutputSurface);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_