Standardize usage of virtual/override/final in ui/

ui/gl/gl_context_cgl.h

Index: ui/gl/gl_context_cgl.h
diff --git a/ui/gl/gl_context_cgl.h b/ui/gl/gl_context_cgl.h
index 5bcb335d5d06c0b64c8515880ac793f75e7524c1..beeb9f90a3a36232ba0af6237f056a610725ae34 100644
--- a/ui/gl/gl_context_cgl.h
+++ b/ui/gl/gl_context_cgl.h
@@ -19,19 +19,19 @@ class GLContextCGL : public GLContextReal {
   explicit GLContextCGL(GLShareGroup* share_group);
 
   // Implement GLContext.
-  virtual bool Initialize(GLSurface* compatible_surface,
-                          GpuPreference gpu_preference) override;
-  virtual void Destroy() override;
-  virtual bool MakeCurrent(GLSurface* surface) override;
-  virtual void ReleaseCurrent(GLSurface* surface) override;
-  virtual bool IsCurrent(GLSurface* surface) override;
-  virtual void* GetHandle() override;
-  virtual void SetSwapInterval(int interval) override;
-  virtual bool GetTotalGpuMemory(size_t* bytes) override;
-  virtual void SetSafeToForceGpuSwitch() override;
+  bool Initialize(GLSurface* compatible_surface,
+                  GpuPreference gpu_preference) override;
+  void Destroy() override;
+  bool MakeCurrent(GLSurface* surface) override;
+  void ReleaseCurrent(GLSurface* surface) override;
+  bool IsCurrent(GLSurface* surface) override;
+  void* GetHandle() override;
+  void SetSwapInterval(int interval) override;
+  bool GetTotalGpuMemory(size_t* bytes) override;
+  void SetSafeToForceGpuSwitch() override;
 
  protected:
-  virtual ~GLContextCGL();
+  ~GLContextCGL() override;
 
  private:
   GpuPreference GetGpuPreference();