Use @Native annotation on dart2js DOM native classes

tools/dom/templates/html/dartium/impl_KeyboardEvent.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_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
+$(ANNOTATIONS)$(NATIVESPEC)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS {
 
   factory $CLASSNAME(String type,
       {Window view, bool canBubble: true, bool cancelable: true,
       int keyLocation: 1, bool ctrlKey: false,
       bool altKey: false, bool shiftKey: false, bool metaKey: false,
       bool altGraphKey: false}) {
     if (view == null) {
       view = window;
     }
     final e = document._createEvent("KeyboardEvent");
     e._initKeyboardEvent(type, canBubble, cancelable, view, "",
         keyLocation, ctrlKey, altKey, shiftKey, metaKey, altGraphKey);
     return e;
   }
 
   @DomName('KeyboardEvent.keyCode')
   int get keyCode => _keyCode;
 
   @DomName('KeyboardEvent.charCode')
   int get charCode => _charCode;
 $!MEMBERS
 }