Standardize usage of virtual/override/final in gpu/

gpu/command_buffer/service/async_pixel_transfer_manager.h

Index: gpu/command_buffer/service/async_pixel_transfer_manager.h
diff --git a/gpu/command_buffer/service/async_pixel_transfer_manager.h b/gpu/command_buffer/service/async_pixel_transfer_manager.h
index 66b8bf7b1efe0cb7b50049d814debbb41cb181f8..3f52e1ec3a23256accb64f3dba2adcf0b7fab7f0 100644
--- a/gpu/command_buffer/service/async_pixel_transfer_manager.h
+++ b/gpu/command_buffer/service/async_pixel_transfer_manager.h
@@ -45,7 +45,7 @@ class GPU_EXPORT AsyncPixelTransferManager
  public:
   static AsyncPixelTransferManager* Create(gfx::GLContext* context);
 
-  virtual ~AsyncPixelTransferManager();
+  ~AsyncPixelTransferManager() override;
 
   void Initialize(gles2::TextureManager* texture_manager);
 
@@ -82,9 +82,8 @@ class GPU_EXPORT AsyncPixelTransferManager
   bool AsyncTransferIsInProgress(gles2::TextureRef* ref);
 
   // gles2::TextureRef::DestructionObserver implementation:
-  virtual void OnTextureManagerDestroying(gles2::TextureManager* manager)
-      override;
-  virtual void OnTextureRefDestroying(gles2::TextureRef* texture) override;
+  void OnTextureManagerDestroying(gles2::TextureManager* manager) override;
+  void OnTextureRefDestroying(gles2::TextureRef* texture) override;
 
  protected:
   AsyncPixelTransferManager();