Fixed dart2js compilation problem

tools/dom/templates/html/impl/impl_CanvasRenderingContext2D.darttemplate

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of $LIBRARYNAME;
 
 abstract class CanvasRenderingContext {
   CanvasElement get canvas;
 }
 
 $(ANNOTATIONS)$(NATIVESPEC)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS implements CanvasRenderingContext {
 $!MEMBERS
 
   @DomName('CanvasRenderingContext2D.createImageDataFromImageData')
   @DocsEditable()
   ImageData createImageDataFromImageData(ImageData imagedata) =>
 $if DART2JS
-    JS('ImageData', '#.createImageData(#, #, null)', this, imagedata);
+    JS('ImageData', '#.createImageData(#)', this, imagedata);
 $else
     this.createImageData(imagedata);
 $endif
 
   /**
    * Sets the color used inside shapes.
    * [r], [g], [b] are 0-255, [a] is 0-1.
    */
   void setFillColorRgb(int r, int g, int b, [num a = 1]) {
     this.fillStyle = 'rgba($r, $g, $b, $a)';
@@ skipping 348 matching lines @@
     JS('void', '#.fill(#)', this, winding);
   }
 $endif
 
   /** Deprecated always returns 1.0 */
   @DomName('CanvasRenderingContext2D.webkitBackingStorePixelRation')
   @Experimental()
   @deprecated
   double get backingStorePixelRatio => 1.0;
 }