gdata: Fix a crash when adding a new file to a new but deleted directory.

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_
 #pragma once
 
 #include <sys/stat.h>
 
@@ skipping 876 matching lines @@
   // Updates whole directory structure feeds collected in |feed_list|.
   // On success, returns PLATFORM_FILE_OK. Record file statistics as UMA
   // histograms.
   base::PlatformFileError UpdateFromFeed(
       const std::vector<DocumentFeed*>& feed_list,
       ContentOrigin origin,
       int largest_changestamp,
       int root_feed_changestamp);
 
   // Applies the pre-processed feed from |file_map| map onto the file system.
+  // All entries in |file_map| will be erased (i.e. the map becomes empty),
+  // and values are deleted.
   void ApplyFeedFromFileUrlMap(bool is_delta_feed,
                                int feed_changestamp,
-                               const FileResourceIdMap& file_map);
+                               FileResourceIdMap* file_map);
 
   // Finds directory where new |file| should be added to during feed processing.
   // |orphaned_entries_dir| collects files/dirs that don't have a parent in
   // either locally cached file system or in this new feed.
   GDataDirectory* FindDirectoryForNewEntry(
       GDataEntry* new_entry,
       const FileResourceIdMap& file_map,
       GDataRootDirectory* orphaned_entries);
 
   // Converts list of document feeds from collected feeds into
@@ skipping 589 matching lines @@
 };
 
 // Sets the free disk space getter for testing.
 // The existing getter is deleted.
 void SetFreeDiskSpaceGetterForTesting(
     FreeDiskSpaceGetterInterface* getter);
 
 }  // namespace gdata
 
 #endif  // CHROME_BROWSER_CHROMEOS_GDATA_GDATA_FILE_SYSTEM_H_