Oilpan: move 2D Canvas and WebGL objects to the heap.

Source/core/html/canvas/WebGLContextAttributes.cpp

Index: Source/core/html/canvas/WebGLContextAttributes.cpp
diff --git a/Source/core/html/canvas/WebGLContextAttributes.cpp b/Source/core/html/canvas/WebGLContextAttributes.cpp
index a26ee33a1332f45989fef7bac92c7d885127b206..9428eaf4d7585a477206ac81502512b2fd7db7f0 100644
--- a/Source/core/html/canvas/WebGLContextAttributes.cpp
+++ b/Source/core/html/canvas/WebGLContextAttributes.cpp
@@ -32,9 +32,11 @@
 
 namespace blink {
 
-PassRefPtr<WebGLContextAttributes> WebGLContextAttributes::create()
+DEFINE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(WebGLContextAttributes);
+
+PassRefPtrWillBeRawPtr<WebGLContextAttributes> WebGLContextAttributes::create()
 {
-    return adoptRef(new WebGLContextAttributes());
+    return adoptRefWillBeNoop(new WebGLContextAttributes());
 }
 
 WebGLContextAttributes::WebGLContextAttributes()
@@ -63,13 +65,9 @@ WebGLContextAttributes::WebGLContextAttributes(const WebGLContextAttributes& att
     ScriptWrappable::init(this);
 }
 
-WebGLContextAttributes::~WebGLContextAttributes()
-{
-}
-
-PassRefPtr<WebGLContextAttributes> WebGLContextAttributes::clone() const
+PassRefPtrWillBeRawPtr<WebGLContextAttributes> WebGLContextAttributes::clone() const
 {
-    return adoptRef(new WebGLContextAttributes(*this));
+    return adoptRefWillBeNoop(new WebGLContextAttributes(*this));
 }
 
 bool WebGLContextAttributes::alpha() const