[SyncFS] Add completion callback to PromoteDemotedChanges (1/3)

chrome/browser/sync_file_system/sync_file_system_service.cc

Index: chrome/browser/sync_file_system/sync_file_system_service.cc
diff --git a/chrome/browser/sync_file_system/sync_file_system_service.cc b/chrome/browser/sync_file_system/sync_file_system_service.cc
index 6789e990e690c4cbe307f64495bfcbe9984806ce..910b83686de9ce32445939f77ae417f430c88b1d 100644
--- a/chrome/browser/sync_file_system/sync_file_system_service.cc
+++ b/chrome/browser/sync_file_system/sync_file_system_service.cc
@@ -361,7 +361,7 @@ void SyncFileSystemService::OnSyncIdle() {
        iter != remote_sync_runners_.end(); ++iter)
     remote_changes += (*iter)->pending_changes();
   if (remote_changes == 0)
-    local_service_->PromoteDemotedChanges();
+    local_service_->PromoteDemotedChanges(NoopClosure());
 
   int64 local_changes = 0;
   for (ScopedVector<SyncProcessRunner>::iterator iter =
@@ -369,7 +369,7 @@ void SyncFileSystemService::OnSyncIdle() {
        iter != local_sync_runners_.end(); ++iter)
     local_changes += (*iter)->pending_changes();
   if (local_changes == 0 && v2_remote_service_)
-    v2_remote_service_->PromoteDemotedChanges();
+    v2_remote_service_->PromoteDemotedChanges(NoopClosure());
 }
 
 SyncServiceState SyncFileSystemService::GetSyncServiceState() {