DevTools: fix hosted mode

third_party/WebKit/Source/devtools/front_end/workspace/IsolatedFileSystemManager.js

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 74 matching lines @@
 }
 
 WebInspector.IsolatedFileSystemManager.prototype = {
     /**
      * @return {!Promise<!Array<!WebInspector.IsolatedFileSystem>>}
      */
     _requestFileSystems: function()
     {
         var fulfill;
         var promise = new Promise(f => fulfill = f);
+        InspectorFrontendHost.events.addEventListener(InspectorFrontendHostAPI.Events.FileSystemsLoaded, onFileSystemsLoaded, this);
         InspectorFrontendHost.requestFileSystems();
-        InspectorFrontendHost.events.addEventListener(InspectorFrontendHostAPI.Events.FileSystemsLoaded, onFileSystemsLoaded, this);
         return promise;
 
         /**
          * @param {!WebInspector.Event} event
          * @this {WebInspector.IsolatedFileSystemManager}
          */
         function onFileSystemsLoaded(event)
         {
             var fileSystems = /** @type {!Array.<!WebInspector.IsolatedFileSystemManager.FileSystem>} */ (event.data);
             var promises = [];
@@ skipping 246 matching lines @@
         this._callbacks.delete(requestId);
     },
 
     __proto__: WebInspector.Object.prototype
 }
 
 /**
  * @type {!WebInspector.IsolatedFileSystemManager}
  */
 WebInspector.isolatedFileSystemManager;