Support 'Conditional' idl attribute.

client/dom/generated/src/wrapping/_MouseEventWrappingImplementation.dart

 // 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.
 
 // WARNING: Do not edit - generated code.
 
 class _MouseEventWrappingImplementation extends _UIEventWrappingImplementation implements MouseEvent {
   _MouseEventWrappingImplementation() : super() {}
 
   static create__MouseEventWrappingImplementation() native {
@@ skipping 38 matching lines @@
 
   int get screenY() { return _get_screenY(this); }
   static int _get_screenY(var _this) native;
 
   bool get shiftKey() { return _get_shiftKey(this); }
   static bool _get_shiftKey(var _this) native;
 
   Node get toElement() { return _get_toElement(this); }
   static Node _get_toElement(var _this) native;
 
-  int get webkitMovementX() { return _get_webkitMovementX(this); }
-  static int _get_webkitMovementX(var _this) native;
-
-  int get webkitMovementY() { return _get_webkitMovementY(this); }
-  static int _get_webkitMovementY(var _this) native;
-
   int get x() { return _get_x(this); }
   static int _get_x(var _this) native;
 
   int get y() { return _get_y(this); }
   static int _get_y(var _this) native;
 
   void initMouseEvent(String type, bool canBubble, bool cancelable, DOMWindow view, int detail, int screenX, int screenY, int clientX, int clientY, bool ctrlKey, bool altKey, bool shiftKey, bool metaKey, int button, EventTarget relatedTarget) {
     _initMouseEvent(this, type, canBubble, cancelable, view, detail, screenX, screenY, clientX, clientY, ctrlKey, altKey, shiftKey, metaKey, button, relatedTarget);
     return;
   }
   static void _initMouseEvent(receiver, type, canBubble, cancelable, view, detail, screenX, screenY, clientX, clientY, ctrlKey, altKey, shiftKey, metaKey, button, relatedTarget) native;
 
   String get typeName() { return "MouseEvent"; }
 }