Move chrome.fileSystem interface and bindings to //extensions

extensions/renderer/resources/file_system_custom_bindings.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.
 
 // Custom binding for the fileSystem API.
 
 var binding = apiBridge || require('binding').Binding.create('fileSystem');
 var sendRequest = bindingUtil ?
     $Function.bind(bindingUtil.sendRequest, bindingUtil) :
     require('sendRequest').sendRequest;
@@ skipping 89 matching lines @@
 
   fileSystem.chooseFile = function() {
     console.log("chrome.fileSystem.chooseFile is deprecated");
     console.log("Please use chrome.fileSystem.chooseEntry instead");
     $Function.apply(fileSystem.chooseEntry, this, arguments);
   };
 });
 
 if (!apiBridge)
   exports.$set('binding', binding.generate());