Update more core classes to use OVERRIDE / FINAL when needed

Source/core/html/canvas/WebGLRenderingContext.h

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 79 matching lines @@
 class WebGLVertexArrayObjectOES;
 
 class WebGLRenderingContextLostCallback;
 class WebGLRenderingContextErrorMessageCallback;
 
 class WebGLRenderingContext FINAL : public CanvasRenderingContext, public ActiveDOMObject, private Page::MultisamplingChangedObserver {
 public:
     static PassOwnPtr<WebGLRenderingContext> create(HTMLCanvasElement*, WebGLContextAttributes*);
     virtual ~WebGLRenderingContext();
 
-    virtual bool is3d() const { return true; }
+    virtual bool is3d() const OVERRIDE { return true; }
     virtual bool isAccelerated() const OVERRIDE { return true; }
 
     int drawingBufferWidth() const;
     int drawingBufferHeight() const;
 
     void activeTexture(GLenum texture);
     void attachShader(WebGLProgram*, WebGLShader*);
     void bindAttribLocation(WebGLProgram*, GLuint index, const String& name);
     void bindBuffer(GLenum target, WebGLBuffer*);
     void bindFramebuffer(GLenum target, WebGLFramebuffer*);
@@ skipping 813 matching lines @@
     // If the vector is empty, return the maximum allowed active context number.
     static size_t oldestContextIndex();
     static IntSize oldestContextSize();
 };
 
 DEFINE_TYPE_CASTS(WebGLRenderingContext, CanvasRenderingContext, context, context->is3d(), context.is3d());
 
 } // namespace WebCore
 
 #endif