Use @Native annotation on dart2js DOM native classes

tools/dom/templates/html/impl/impl_ShadowRoot.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.
 
 // WARNING: Do not edit - generated code.
 
 part of $LIBRARYNAME;
 
-$(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
+$(ANNOTATIONS)$(NATIVESPEC)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS {
 $!MEMBERS
 $if DART2JS
   static bool get supported =>
       JS('bool', '!!(Element.prototype.createShadowRoot||'
                  'Element.prototype.webkitCreateShadowRoot)');
 $else
   static final bool supported = true;
 $endif
 
   static bool _shadowRootDeprecationReported = false;
@@ skipping 24 matching lines @@
     _shadowRootDeprecationReport();
     // Default value from when it was specified.
     return false;
   }
 
   @deprecated
   void set applyAuthorStyles(bool value) {
     _shadowRootDeprecationReport();
   }
 }