[fsp] Extract common code to FileSystemProvidedInternalFunction.

chrome/common/extensions/api/file_system_provider.idl

 // Copyright 2013 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.
 
 // Use the <code>chrome.fileSystemProvider</code> API to create file systems,
 // that can be accessible from the file manager on Chrome OS.
 [platforms=("chromeos"),
  implemented_in="chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.h"]
 namespace fileSystemProvider {
   // Error codes used by providing extensions in response to requests. For
@@ skipping 84 matching lines @@
     // Raised when unmounting for the file system with the <code>fileSystemId
     // </code> identifier is requested. In response, the <code>unmount</code>
     // API method should be called together with <code>successCallback</code>.
     // If unmounting is not possible (eg. due to a pending operation), then
     // <code>errorCallback</code> must be called.
     [maxListeners=1] static void onUnmountRequested(
         long fileSystemId,
         ProviderSuccessCallback successCallback,
         ProviderErrorCallback errorCallback);
 
-    // Raised, when metadata of a file or a directory at <code>entryPath</code>
+    // Raised when metadata of a file or a directory at <code>entryPath</code>
     // is requested. The metadata should be returned with the <code>
     // successCallback</code> call. In case of an error, <code>errorCallback
     // </code> must be called.
     [maxListeners=1] static void onGetMetadataRequested(
         long fileSystemId,
         DOMString entryPath,
         MetadataCallback successCallback,
         ErrorCallback errorCallback);
   };
 };