Syncing CssStyleDeclaration.setPropertyValue's signature between dart2js and dartium

tools/dom/templates/html/impl/impl_CSSStyleDeclaration.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;
 
 $(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
   factory $CLASSNAME() => _$(CLASSNAME)FactoryProvider.create$CLASSNAME();
   factory $CLASSNAME.css(String css) =>
       _$(CLASSNAME)FactoryProvider.create$(CLASSNAME)_css(css);
 
 $!MEMBERS
 
   String getPropertyValue(String propertyName) {
     var propValue = _getPropertyValue(propertyName);
     return propValue != null ? propValue : '';
   }
 
 $if DART2JS
+  @DomName('CSSStyleDeclaration.setProperty')
   void setProperty(String propertyName, String value, [String priority]) {
     // try/catch for IE9 which throws on unsupported values.
     try {
+      if (priority == null) {
+        priority = '';
+      }
       JS('void', '#.setProperty(#, #, #)', this, propertyName, value, priority);
       // Bug #2772, IE9 requires a poke to actually apply the value.
       if (JS('bool', '!!#.setAttribute', this)) {
         JS('void', '#.setAttribute(#, #)', this, propertyName, value);
       }
     } catch (e) {}
   }
 
   /**
    * Checks to see if CSS Transitions are supported.
    */
   static bool get supportsTransitions {
     if (JS('bool', '"transition" in document.body.style')) {
       return true;
     }
     var propertyName = '${Device.propertyPrefix}Transition';
     return JS('bool', '# in document.body.style', propertyName);
   }
 $else
   /**
    * Checks to see if CSS Transitions are supported.
    */
   static bool get supportsTransitions => true;
+
+  @DomName('CSSStyleDeclaration.setProperty')
+  void setProperty(String propertyName, String value, [String priority]) {
+    if (priority == null) {
+      priority = '';
+    }
+    _setProperty(propertyName, value, priority);
+  }
 $endif
 
   // TODO(jacobr): generate this list of properties using the existing script.
   /** Gets the value of "align-content" */
   String get alignContent =>
     getPropertyValue('${Device.cssPrefix}align-content');
 
   /** Sets the value of "align-content" */
   void set alignContent(String value) {
     setProperty('${Device.cssPrefix}align-content', value, '');
@@ skipping 3141 matching lines @@
 
   /** Gets the value of "zoom" */
   String get zoom =>
     getPropertyValue('zoom');
 
   /** Sets the value of "zoom" */
   void set zoom(String value) {
     setProperty('zoom', value, '');
   }
 }