gdata: Make callback parameter mandatory for GetEntryInfo family

chrome/browser/chromeos/gdata/gdata_file_system.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_GDATA_GDATA_FILE_SYSTEM_H_
 #define CHROME_BROWSER_CHROMEOS_GDATA_GDATA_FILE_SYSTEM_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 524 matching lines @@
 
   // Callback for handling results of ReloadFeedFromServerIfNeeded() initiated
   // from CheckForUpdates(). This callback checks whether feed is successfully
   // reloaded, and in case of failure, restores the content origin of the root
   // directory.
   void OnUpdateChecked(ContentOrigin initial_origin,
                        GDataFileError error,
                        GDataEntry* entry);
 
   // Runs the callback and notifies that the initial load is finished.
+  // |callback| must not be null.
   void RunAndNotifyInitialLoadFinished(const FindEntryCallback& callback,
                                        GDataFileError error,
                                        GDataEntry* entry);
 
   // Helper function that completes bookkeeping tasks related to
   // completed file transfer.
   void OnTransferCompleted(const FileOperationCallback& callback,
                            GDataFileError error,
                            scoped_ptr<UploadFileInfo> upload_file_info);
 
@@ skipping 36 matching lines @@
                           scoped_ptr<base::Value> data);
 
   // Starts downloading a file if we have enough disk space indicated by
   // |has_enough_space|.
   void StartDownloadFileIfEnoughSpace(const GetFileFromCacheParams& params,
                                       const GURL& content_url,
                                       const FilePath& cache_file_path,
                                       bool* has_enough_space);
 
   // Helper function used to perform synchronous file search on UI thread.
+  // |callback| must not be null.
   void FindEntryByPathSyncOnUIThread(const FilePath& search_file_path,
                                      const FindEntryCallback& callback);
 
   // Changes state of hosted documents visibility, triggers directory refresh.
   void SetHideHostedDocuments(bool hide);
 
   // Initializes preference change observer.
   void InitializePreferenceObserver();
 
   // Called when an entry is found for GetEntryInfoByPath().
+  // |callback| must not be null.
   void OnGetEntryInfo(const GetEntryInfoCallback& callback,
                       GDataFileError error,
                       GDataEntry* entry);
 
   // Called when an entry is found for ReadDirectoryByPath().
+  // |callback| must not be null.
   void OnReadDirectory(const ReadDirectoryWithSettingCallback& callback,
                        GDataFileError error,
                        GDataEntry* entry);
 
   // Finds file info by using virtual |file_path|. This call will also
   // retrieve and refresh file system content from server and disk cache.
+  // |callback| must not be null.
   void FindEntryByPathAsyncOnUIThread(const FilePath& search_file_path,
                                       const FindEntryCallback& callback);
 
   // Gets |file_path| from the file system after the file info is already
   // resolved with GetEntryInfoByPath(). This function is called by
   // OnGetEntryInfoCompleteForGetFileByPath and
   // OnGetEntryInfoCompleteForOpenFile.
   void GetResolvedFileByPath(
       const FilePath& file_path,
       const GetFileCallback& get_file_callback,
@@ skipping 124 matching lines @@
   // Part of RequestDirectoryRefreshOnUIThread(). Called after
   // GetEntryInfoByPath() is complete.
   void RequestDirectoryRefreshOnUIThreadAfterGetEntryInfo(
       const FilePath& file_path,
       GDataFileError error,
       scoped_ptr<GDataEntryProto> entry_proto);
 
   // Part of GetEntryByResourceId and GetEntryByPath. Checks whether there is a
   // local dirty cache for the entry, and if there is, replace the
   // PlatformFileInfo part of the |entry_proto| with the locally modified info.
+  // |callback| must not be null.
   void CheckLocalModificationAndRun(scoped_ptr<GDataEntryProto> entry_proto,
                                     const GetEntryInfoCallback& callback);
   void CheckLocalModificationAndRunAfterGetCacheEntry(
       scoped_ptr<GDataEntryProto> entry_proto,
       const GetEntryInfoCallback& callback,
       bool success,
       const GDataCacheEntry& cache_entry);
   void CheckLocalModificationAndRunAfterGetCacheFile(
       scoped_ptr<GDataEntryProto> entry_proto,
       const GetEntryInfoCallback& callback,
@@ skipping 49 matching lines @@
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<GDataFileSystem> ui_weak_ptr_factory_;
   // Unlike other classes, we need this as we need this to redirect a task
   // from IO thread to UI thread.
   base::WeakPtr<GDataFileSystem> ui_weak_ptr_;
 };
 
 }  // namespace gdata
 
 #endif  // CHROME_BROWSER_CHROMEOS_GDATA_GDATA_FILE_SYSTEM_H_