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

cc/surfaces/display.h

Index: cc/surfaces/display.h
diff --git a/cc/surfaces/display.h b/cc/surfaces/display.h
index fd847f4e2eeb6442fe4186d6cd734d61345ab030..6b32ee92df4d1dc3840d64ea13ad554181579f93 100644
--- a/cc/surfaces/display.h
+++ b/cc/surfaces/display.h
@@ -87,7 +87,6 @@ class CC_SURFACES_EXPORT Display : public DisplaySchedulerClient,
   void DidReceiveSwapBuffersAck() override;
   void DidReceiveTextureInUseResponses(
       const gpu::TextureInUseResponses& responses) override;
-  void DidLoseOutputSurface() override;
 
   // SurfaceObserver implementation.
   void OnSurfaceDamaged(const SurfaceId& surface, bool* changed) override;
@@ -103,6 +102,7 @@ class CC_SURFACES_EXPORT Display : public DisplaySchedulerClient,
  private:
   void InitializeRenderer();
   void UpdateRootSurfaceResourcesLocked();
+  void DidLoseContextProvider();
 
   SharedBitmapManager* const bitmap_manager_;
   gpu::GpuMemoryBufferManager* const gpu_memory_buffer_manager_;