Remove old feature for generating canned native bodies.

lib/dom/dart2js/dom_dart2js.dart

 #library('dart:dom_deprecated');
 
 // Copyright (c) 2011, 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.
 
 // DO NOT EDIT
 // Auto-generated Dart DOM library.
 
 
@@ skipping 4203 matching lines @@
   final String direction;
 
   final key;
 
   final primaryKey;
 
   final source;
 
   void advance(int count) native;
 
-  void continueFunction([key]) native '''
-        if (key == null) return this['continue']();
-        return this['continue'](key);
-      ''';
+  void continueFunction([key]) native 'continue';
 
   _IDBRequestJs delete() native;
 
   _IDBRequestJs update(value) native;
 }
 
 class _IDBCursorWithValueJs extends _IDBCursorJs implements IDBCursorWithValue native "*IDBCursorWithValue" {
 
   final value;
 }
@@ skipping 21241 matching lines @@
     if (length < 0) throw new IllegalArgumentException('length');
     if (start < 0) throw new IndexOutOfRangeException(start);
     int end = start + length;
     if (end > a.length) throw new IndexOutOfRangeException(end);
     for (int i = start; i < end; i++) {
       accumulator.add(a[i]);
     }
     return accumulator;
   }
 }