Split DirectCompositionSurfaceWin into two parts.

gpu/ipc/service/direct_composition_surface_win.h

Index: gpu/ipc/service/direct_composition_surface_win.h
diff --git a/gpu/ipc/service/direct_composition_surface_win.h b/gpu/ipc/service/direct_composition_surface_win.h
index e2121eaaca0aacec70b95e26959181bd322e08af..ebc5f03cf6ae9ec23e29a3a405ba79ca25a7c72e 100644
--- a/gpu/ipc/service/direct_composition_surface_win.h
+++ b/gpu/ipc/service/direct_composition_surface_win.h
@@ -21,6 +21,7 @@
 namespace gpu {
 
 class DCLayerTree;
+class DirectCompositionChildSurfaceWin;
 
 class GPU_EXPORT DirectCompositionSurfaceWin : public gl::GLSurfaceEGL {
  public:
@@ -64,14 +65,10 @@ class GPU_EXPORT DirectCompositionSurfaceWin : public gl::GLSurfaceEGL {
   // tree at z-order 0.
   bool ScheduleDCLayer(const ui::DCRendererLayerParams& params) override;
 
-  const base::win::ScopedComPtr<IDCompositionSurface>& dcomp_surface() const {
-    return dcomp_surface_;
-  }
+  const base::win::ScopedComPtr<IDCompositionSurface> dcomp_surface() const;
+  const base::win::ScopedComPtr<IDXGISwapChain1> swap_chain() const;
 
   scoped_refptr<base::TaskRunner> GetWindowTaskRunnerForTesting();
-  const base::win::ScopedComPtr<IDXGISwapChain1>& swap_chain() const {
-    return swap_chain_;
-  }
 
   base::win::ScopedComPtr<IDXGISwapChain1> GetLayerSwapChainForTesting(
       size_t index) const;
@@ -82,12 +79,7 @@ class GPU_EXPORT DirectCompositionSurfaceWin : public gl::GLSurfaceEGL {
   ~DirectCompositionSurfaceWin() override;
 
  private:
-  void ReleaseCurrentSurface();
-  void InitializeSurface();
-  // Release the texture that's currently being drawn to. If will_discard is
-  // true then the surface should be discarded without swapping any contents
-  // to it.
-  void ReleaseDrawTexture(bool will_discard);
+  bool RecreateRootSurface();
 
   ChildWindowWin child_window_;
 
@@ -98,27 +90,15 @@ class GPU_EXPORT DirectCompositionSurfaceWin : public gl::GLSurfaceEGL {
   // DirectComposition surface.
   EGLSurface default_surface_ = 0;
 
-  // This is the real surface representing the backbuffer. It may be null
-  // outside of a BeginDraw/EndDraw pair.
-  EGLSurface real_surface_ = 0;
   gfx::Size size_ = gfx::Size(1, 1);
-  bool first_swap_ = true;
   bool enable_dc_layers_ = false;
   bool has_alpha_ = true;
   std::unique_ptr<gfx::VSyncProvider> vsync_provider_;
-  gfx::Rect swap_rect_;
+  scoped_refptr<DirectCompositionChildSurfaceWin> root_surface_;
   std::unique_ptr<DCLayerTree> layer_tree_;
-  gfx::Vector2d draw_offset_;
 
   base::win::ScopedComPtr<ID3D11Device> d3d11_device_;
   base::win::ScopedComPtr<IDCompositionDevice2> dcomp_device_;
-  base::win::ScopedComPtr<IDCompositionSurface> dcomp_surface_;
-  base::win::ScopedComPtr<IDXGISwapChain1> swap_chain_;
-  base::win::ScopedComPtr<ID3D11Texture2D> draw_texture_;
-
-  // Keep track of whether the texture has been rendered to, as the first draw
-  // to it must overwrite the entire thing.
-  bool has_been_rendered_to_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(DirectCompositionSurfaceWin);
 };