cc: Make OutputSurface::BindToClient pure virtual and not return bool

content/browser/compositor/offscreen_browser_compositor_output_surface.h

 // Copyright 2015 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_OFFSCREEN_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
 #define CONTENT_BROWSER_COMPOSITOR_OFFSCREEN_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 17 matching lines @@
  public:
   OffscreenBrowserCompositorOutputSurface(
       scoped_refptr<ContextProviderCommandBuffer> context,
       scoped_refptr<ui::CompositorVSyncManager> vsync_manager,
       cc::SyntheticBeginFrameSource* begin_frame_source,
       std::unique_ptr<display_compositor::CompositorOverlayCandidateValidator>
           overlay_candidate_validator);
 
   ~OffscreenBrowserCompositorOutputSurface() override;
 
- protected:
-  // cc::OutputSurface:
+ private:
+  // cc::OutputSurface implementation.
+  void BindToClient(cc::OutputSurfaceClient* client) override;
   void EnsureBackbuffer() override;
   void DiscardBackbuffer() override;
   void Reshape(const gfx::Size& size,
                float scale_factor,
                const gfx::ColorSpace& color_space,
                bool alpha) override;
   void BindFramebuffer() override;
   void SwapBuffers(cc::OutputSurfaceFrame frame) override;
   bool IsDisplayedAsOverlayPlane() const override;
   unsigned GetOverlayTextureId() const override;
   bool SurfaceIsSuspendForRecycle() const override;
   uint32_t GetFramebufferCopyTextureFormat() override;
 
-  // BrowserCompositorOutputSurface
+  // BrowserCompositorOutputSurface implementation.
   void OnReflectorChanged() override;
 #if defined(OS_MACOSX)
   void SetSurfaceSuspendedForRecycle(bool suspended) override {};
 #endif
 
+  void OnSwapBuffersComplete();
+
+  cc::OutputSurfaceClient* client_ = nullptr;
   gfx::Size reshape_size_;
   uint32_t fbo_ = 0;
   bool reflector_changed_ = false;
   std::unique_ptr<ReflectorTexture> reflector_texture_;
-
   base::WeakPtrFactory<OffscreenBrowserCompositorOutputSurface>
       weak_ptr_factory_;
 
- private:
-  void OnSwapBuffersComplete();
-
   DISALLOW_COPY_AND_ASSIGN(OffscreenBrowserCompositorOutputSurface);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_OFFSCREEN_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_