Sync FileSystem: Mark empty batch sync origin as incremental sync origin.

chrome/browser/sync_file_system/drive_file_sync_service.cc

Index: chrome/browser/sync_file_system/drive_file_sync_service.cc
diff --git a/chrome/browser/sync_file_system/drive_file_sync_service.cc b/chrome/browser/sync_file_system/drive_file_sync_service.cc
index 84222cecad3aadaa65c0ce986420ee90db9705d1..91c58b9374ec56e3b9de7f5f44e9e1db77e01d1d 100644
--- a/chrome/browser/sync_file_system/drive_file_sync_service.cc
+++ b/chrome/browser/sync_file_system/drive_file_sync_service.cc
@@ -887,6 +887,11 @@ void DriveFileSyncService::DidGetDirectoryContentForBatchSync(
     return;
   }
 
+  if (metadata_store_->IsBatchSyncOrigin(origin) &&
+      !ContainsKey(url_to_change_, origin)) {

[kinuko, 2013/01/04 10:38:54]

This is not directly related to this change, but can we rename 'url_to_change_'
(and its type name) to 'origin_to_change_map_' or 'origin_to_changes_'?

[tzik, 2013/01/07 08:37:55]

Let me rename to 'origin_to_changes_map_'.
Its type is Origin -> Path -> Change or (Origin, Path) -> Change.

+    metadata_store_->MoveBatchSyncOriginToIncremental(origin);
+  }
+
   NotifyTaskDone(fileapi::SYNC_STATUS_OK, token.Pass());
 }