Moved the majority of WebGL functionality into WebGLRenderingContextBase

Source/core/html/canvas/OESStandardDerivatives.h

Index: Source/core/html/canvas/OESStandardDerivatives.h
diff --git a/Source/core/html/canvas/OESStandardDerivatives.h b/Source/core/html/canvas/OESStandardDerivatives.h
index eee4ab55e282baea2ae5c4fd7fb73206d2cb6f08..f0264df3dcf8c46a7934ae926312fc327a3e2d0f 100644
--- a/Source/core/html/canvas/OESStandardDerivatives.h
+++ b/Source/core/html/canvas/OESStandardDerivatives.h
@@ -34,15 +34,15 @@ namespace WebCore {
 
 class OESStandardDerivatives : public WebGLExtension, public ScriptWrappable {
 public:
-    static PassRefPtr<OESStandardDerivatives> create(WebGLRenderingContext*);
-    static bool supported(WebGLRenderingContext*);
+    static PassRefPtr<OESStandardDerivatives> create(WebGLRenderingContextBase*);
+    static bool supported(WebGLRenderingContextBase*);
     static const char* getExtensionName();
 
     virtual ~OESStandardDerivatives();
     virtual ExtensionName getName() const;
 
 private:
-    OESStandardDerivatives(WebGLRenderingContext*);
+    OESStandardDerivatives(WebGLRenderingContextBase*);
 };
 
 } // namespace WebCore