Use @Native annotation on dart2js DOM native classes

tools/dom/templates/html/dart2js/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.
 
 
 /**
  * An event that describes user interaction with the keyboard.
  *
  * The [type] of the event identifies what kind of interaction occurred.
  *
  * See also:
  *
  * * [KeyboardEvent](https://developer.mozilla.org/en/DOM/KeyboardEvent) at MDN.
  */
-$(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
+$(ANNOTATIONS)$(NATIVESPEC)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS {

[blois, 2014/07/22 20:44:10]

Why not just put it in the annotations list?

[sra1, 2014/07/22 22:47:06]

Some templates had explicit 'native' clauses which means the @Native must be
specified in the template too.

It would be a reasonable change but I'd like to keep this CL is as mechanical as
possible.

 
   /** 
    * Programmatically create a KeyboardEvent. 
    *
    * Due to browser differences, keyCode, charCode, or keyIdentifier values
    * cannot be specified in this base level constructor. This constructor
    * enables the user to programmatically create and dispatch a [KeyboardEvent],
    * but it will not contain any particular key content. For programmatically
    * creating keyboard events with specific key value contents, see the custom
    * Event [KeyEvent]. 
@@ skipping 32 matching lines @@
     }
   }
 
   @DomName('KeyboardEvent.keyCode')
   int get keyCode => _keyCode;
 
   @DomName('KeyboardEvent.charCode')
   int get charCode => _charCode;
 $!MEMBERS
 }