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

chrome/browser/sync_file_system/local/local_file_change_tracker.h

Index: chrome/browser/sync_file_system/local/local_file_change_tracker.h
diff --git a/chrome/browser/sync_file_system/local/local_file_change_tracker.h b/chrome/browser/sync_file_system/local/local_file_change_tracker.h
index 20e62cdcdcb94e995bc244c18691c6ce7192886d..34fd457fbd387194e9fbab899f2e2192249a4bbe 100644
--- a/chrome/browser/sync_file_system/local/local_file_change_tracker.h
+++ b/chrome/browser/sync_file_system/local/local_file_change_tracker.h
@@ -97,6 +97,9 @@ class LocalFileChangeTracker
   // 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();