Mac: Fix black flashing during tab switch

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 "base/cancelable_callback.h"
 #include "content/browser/compositor/browser_compositor_output_surface.h"
 
@@ skipping 19 matching lines @@
 
   ~GpuBrowserCompositorOutputSurface() override;
 
  protected:
   // cc::OutputSurface implementation.
   void SwapBuffers(cc::CompositorFrame* frame) override;
   bool BindToClient(cc::OutputSurfaceClient* client) override;
 
 #if defined(OS_MACOSX)
   void OnSurfaceDisplayed() override;
-  void OnSurfaceRecycled() override;
-  bool ShouldNotShowFramesAfterRecycle() const override;
-  bool should_not_show_frames_;
+  void SetSurfaceSuspendedForRecycle(bool suspended) override;
+  bool SurfaceShouldNotShowFramesAfterSuspendForRecycle() const override;
+  enum ShouldShowFramesState {
+    // Frames that come from the GPU process should appear on-screen.
+    SHOULD_SHOW_FRAMES,
+    // The compositor has been suspended. Any frames that come from the GPU
+    // process are for the pre-suspend content and should not be displayed.
+    SHOULD_NOT_SHOW_FRAMES_SUSPENDED,
+    // The compositor has been un-suspended, but has not yet issued a swap
+    // since being un-suspended, so any frames that come from the GPU process
+    // are for pre-suspend content and should not be displayed.
+    SHOULD_NOT_SHOW_FRAMES_NO_SWAP_AFTER_SUSPENDED,
+  };
+  ShouldShowFramesState should_show_frames_state_;
 #endif
 
   CommandBufferProxyImpl* GetCommandBufferProxy();
   void OnSwapBuffersCompleted(const std::vector<ui::LatencyInfo>& latency_info);
 
   base::CancelableCallback<void(const std::vector<ui::LatencyInfo>&)>
       swap_buffers_completion_callback_;
   base::CancelableCallback<void(base::TimeTicks timebase,
                                 base::TimeDelta interval)>
       update_vsync_parameters_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuBrowserCompositorOutputSurface);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_