Adding Blink bindings for WebGL 2

Source/core/html/canvas/WebGLRenderingContextBase.h

Index: Source/core/html/canvas/WebGLRenderingContextBase.h
diff --git a/Source/core/html/canvas/WebGLRenderingContextBase.h b/Source/core/html/canvas/WebGLRenderingContextBase.h
index 919b14380f95cec58ec6ea95f01c52fb8393216f..7f6f01e1bf811f9f8d430340c94cfb3fe496543b 100644
--- a/Source/core/html/canvas/WebGLRenderingContextBase.h
+++ b/Source/core/html/canvas/WebGLRenderingContextBase.h
@@ -115,6 +115,9 @@ public:
 
     static unsigned getWebGLVersion(const CanvasRenderingContext*);
 
+    static PassOwnPtr<blink::WebGraphicsContext3D> createWebGraphicsContext3D(HTMLCanvasElement*, WebGLContextAttributes, unsigned webGLVersion);
+    static void forceNextWebGLContextCreationToFail();
+
     int drawingBufferWidth() const;
     int drawingBufferHeight() const;
 
@@ -421,6 +424,8 @@ protected:
     bool paintRenderingResultsToCanvas(SourceDrawingBuffer) override;
     virtual blink::WebLayer* platformLayer() const override;
 
+    bool isWebGL2OrHigher() { return version() >= 2; }
+
     void addSharedObject(WebGLSharedObject*);
     void addContextObject(WebGLContextObject*);
     void detachAndRemoveAllObjects();