Revert "Use @Native annotation on dart2js DOM native classes"

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

 // Copyright (c) 2013, 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;
 
 @Experimental()
-$(ANNOTATIONS)$(NATIVESPEC)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS {
+$(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
 $!MEMBERS
 
   /**
    * An override to place the contents into content rather than as child nodes.
    *
    * See also:
    *
    * * <https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/templates/index.html#innerhtml-on-templates>
    */
   void setInnerHtml(String html,
     {NodeValidator validator, NodeTreeSanitizer treeSanitizer}) {
     text = null;
     var fragment = createFragment(
         html, validator: validator, treeSanitizer: treeSanitizer);
 
     content.append(fragment);
   }
 }