[Chromoting] Move shared webapp JS files from crd/js -> base/js

remoting/webapp/base/js/oauth2.js

 // Copyright (c) 2012 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.
 
 /**
  * @fileoverview
  * OAuth2 class that handles retrieval/storage of an OAuth2 token.
  *
  * Uses a content script to trampoline the OAuth redirect page back into the
  * extension context.  This works around the lack of native support for
@@ skipping 430 matching lines @@
       window.localStorage.setItem(that.KEY_FULLNAME_, name);
       resolve({email: email, name: name});
     };
 
     that.getToken().then(
         remoting.oauth2Api.getUserInfo.bind(
             remoting.oauth2Api, onResponse, reject),
         reject);
   });
 };