gdata: Add requestDirectoryRefresh to file_browser_private.

chrome/common/extensions/api/file_browser_private.json

 // 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.
 
 [
   {
     "namespace":"fileBrowserPrivate",
     "nodoc": "true",
     "types": [
       {
@@ skipping 914 matching lines @@
                 "name": "result",
                 "type": "object",
                 "properties": {
                   "type": {"type": "string"},
                   "online": {"type": "boolean"}
                 }
               }
             ]
           }
         ]
+      },
+      {
+        "name": "requestDirectoryRefresh",
+        "description": "Requests a refresh of a directory. Used to get the latest metadata of files in a particular directory. Upon completion, onFileChanged event is raised against the target directory, so that the file browser can redraw contents in the directory. Note that the onFileChanged event can be raised even if there is no change in the directory as it's expensive to check if the new contents match the existing ones.",
+        "parameters": [
+          {
+            "name": "fileURL",
+            "type": "string",
+            "description": "URL of the target directory"
+          }
+        ]
       }
     ],
     "events": [
       {
         "name": "onDiskChanged",
         "type": "function",
         "description": "Fired when disk mount/unmount event is detected.",
         "parameters": [
           {
             "$ref": "MountEvent",
@@ skipping 59 matching lines @@
       },
       {
         "name": "onNetworkConnectionChanged",
         "type": "function",
         "description": "Fired when the active network connection state changes. The network connection state can be retrieved via 'getNetworkConnectionState'.",
         "parameters": []
       }
     ]
   }
 ]