[SyncFS] Add per-URL promote of demoted changes in LocalFileChangeTracker

chrome/browser/sync_file_system/local/local_file_change_tracker.h

 // 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.
 
 #ifndef CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_CHANGE_TRACKER_H_
 #define CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_CHANGE_TRACKER_H_
 
 #include <deque>
 #include <map>
 #include <string>
@@ skipping 79 matching lines @@
 
   // Resets the changes to the ones recorded in mirror for |url|, and
   // commits the updated change status to database.
   void ResetToMirrorAndCommitChangesForURL(const fileapi::FileSystemURL& url);
 
   // Re-inserts changes into the separate demoted_changes_ queue. They won't
   // be fetched by GetNextChangedURLs() unless PromoteDemotedChanges() is
   // called.
   void DemoteChangesForURL(const fileapi::FileSystemURL& url);
 
+  // Promotes demoted changes for |url| to the normal queue.
+  void PromoteDemotedChangesForURL(const fileapi::FileSystemURL& url);
+
   // Promotes all demoted changes to the normal queue. Returns true if it has
   // promoted any changes.
   bool PromoteDemotedChanges();
 
   // Called by FileSyncService at the startup time to restore last dirty changes
   // left after the last shutdown (if any).
   SyncStatusCode Initialize(fileapi::FileSystemContext* file_system_context);
 
   // Resets all the changes recorded for the given |origin| and |type|.
   // TODO(kinuko,nhiroki): Ideally this should be automatically called in
@@ skipping 71 matching lines @@
   // This can be accessed on any threads (with num_changes_lock_).
   int64 num_changes_;
   mutable base::Lock num_changes_lock_;
 
   DISALLOW_COPY_AND_ASSIGN(LocalFileChangeTracker);
 };
 
 }  // namespace sync_file_system
 
 #endif  // CHROME_BROWSER_SYNC_FILE_SYSTEM_LOCAL_LOCAL_FILE_CHANGE_TRACKER_H_