Standardize usage of virtual/override/final in ui/

ui/gl/gl_context_stub.h

Index: ui/gl/gl_context_stub.h
diff --git a/ui/gl/gl_context_stub.h b/ui/gl/gl_context_stub.h
index c95be1d0c6579a92eec52eaf5663d15ad3575c8a..1a7eb2487840e4b8073b5cdbf5ecaa3ebd9858f4 100644
--- a/ui/gl/gl_context_stub.h
+++ b/ui/gl/gl_context_stub.h
@@ -15,19 +15,19 @@ class GL_EXPORT GLContextStub : public GLContextReal {
   GLContextStub();
 
   // 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 std::string GetExtensions() override;
-  virtual std::string GetGLRenderer() 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;
+  std::string GetExtensions() override;
+  std::string GetGLRenderer() override;
 
  protected:
-  virtual ~GLContextStub();
+  ~GLContextStub() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(GLContextStub);