Update HTML canvas classes to use OVERRIDE / FINAL when needed

Source/core/html/canvas/EXTFragDepth.h

Index: Source/core/html/canvas/EXTFragDepth.h
diff --git a/Source/core/html/canvas/EXTFragDepth.h b/Source/core/html/canvas/EXTFragDepth.h
index fc8a9fa6f8ebf68c7a972a1abc14213d2008be82..3c0563efb6a412fb39a0b1639c772127cb8f9f34 100644
--- a/Source/core/html/canvas/EXTFragDepth.h
+++ b/Source/core/html/canvas/EXTFragDepth.h
@@ -32,14 +32,14 @@
 
 namespace WebCore {
 
-class EXTFragDepth : public WebGLExtension, public ScriptWrappable {
+class EXTFragDepth FINAL : public WebGLExtension, public ScriptWrappable {
 public:
     static PassRefPtr<EXTFragDepth> create(WebGLRenderingContext*);
     static bool supported(WebGLRenderingContext*);
     static const char* extensionName();
 
     virtual ~EXTFragDepth();
-    virtual ExtensionName name() const;
+    virtual ExtensionName name() const OVERRIDE;
 
 private:
     explicit EXTFragDepth(WebGLRenderingContext*);