Implement WEBGL_shared_resources

Source/bindings/v8/custom/V8HTMLCanvasElementCustom.cpp

Index: Source/bindings/v8/custom/V8HTMLCanvasElementCustom.cpp
diff --git a/Source/bindings/v8/custom/V8HTMLCanvasElementCustom.cpp b/Source/bindings/v8/custom/V8HTMLCanvasElementCustom.cpp
index 2d9ef71e41964cd4ad7080f56a1a3a7b25ac20f0..0a0e22d65d09f8f8883a20e7bb13df4850eb6420 100644
--- a/Source/bindings/v8/custom/V8HTMLCanvasElementCustom.cpp
+++ b/Source/bindings/v8/custom/V8HTMLCanvasElementCustom.cpp
@@ -35,6 +35,7 @@
 #include "V8CanvasRenderingContext2D.h"
 #include "V8Node.h"
 #include "V8WebGLRenderingContext.h"
+#include "V8WebGLShareGroup.h"
 #include "bindings/v8/V8Binding.h"
 #include "core/html/HTMLCanvasElement.h"
 #include "core/html/canvas/Canvas2DContextAttributes.h"
@@ -74,6 +75,13 @@ void V8HTMLCanvasElement::getContextMethodCustom(const v8::FunctionCallbackInfo<
             v8::Handle<v8::String> preserveDrawingBuffer = v8::String::NewSymbol("preserveDrawingBuffer");
             if (jsAttrs->Has(preserveDrawingBuffer))
                 webGLAttrs->setPreserveDrawingBuffer(jsAttrs->Get(preserveDrawingBuffer)->BooleanValue());
+            v8::Handle<v8::String> group = v8::String::NewSymbol("group");
+            if (jsAttrs->Has(group)) {
+                v8::Handle<v8::Value> value = jsAttrs->Get(group);
+                if (value->IsObject()) {
+                    webGLAttrs->setGroup(V8WebGLShareGroup::toNative(value->ToObject()));
+                }
+            }
         }
         attrs = webGLAttrs;
     } else {