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

chrome/browser/chromeos/gdata/gdata_file_system.h

Index: chrome/browser/chromeos/gdata/gdata_file_system.h
diff --git a/chrome/browser/chromeos/gdata/gdata_file_system.h b/chrome/browser/chromeos/gdata/gdata_file_system.h
index fb1fdc5557784eb21957a51e9c554568010f4219..2b954008bc9c55bae5bf5bac40c371b024d123e6 100644
--- a/chrome/browser/chromeos/gdata/gdata_file_system.h
+++ b/chrome/browser/chromeos/gdata/gdata_file_system.h
@@ -894,9 +894,11 @@ class GDataFileSystem : public GDataFileSystemInterface,
       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