Dart: Moves |native| methods to patch files.

mojo/public/dart/src/handle.dart

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 part of core;
 
 class _MojoHandleNatives {
-  static int register(MojoEventStream eventStream) native "MojoHandle_Register";
-  static int close(int handle) native "MojoHandle_Close";
-  static List wait(int handle, int signals, int deadline) native
-      "MojoHandle_Wait";
-  static List waitMany(List<int> handles, List<int> signals,
-      int deadline) native "MojoHandle_WaitMany";
+  external static int register(MojoEventStream eventStream);
+  external static int close(int handle);
+  external static List wait(int handle, int signals, int deadline);
+  external static List waitMany(List<int> handles, List<int> signals,
+      int deadline);
 }
 
 
 class MojoHandle {
   static const int INVALID = 0;
   static const int DEADLINE_INDEFINITE = -1;
 
   int h;
 
   MojoHandle(this.h);
@@ skipping 42 matching lines @@
   }
 
   bool get isValid => (h != INVALID);
 
   String toString() => "$h";
 
   bool operator ==(MojoHandle other) {
     return h == other.h;
   }
 }