[SyncFS] Clear dirty flag on changelist application phase

chrome/browser/sync_file_system/drive_backend/metadata_database.h

Index: chrome/browser/sync_file_system/drive_backend/metadata_database.h
diff --git a/chrome/browser/sync_file_system/drive_backend/metadata_database.h b/chrome/browser/sync_file_system/drive_backend/metadata_database.h
index cfd745d94ece7a99ac2d1b8b77c8575b8fa07d33..2f862329d865c03f520f0a091756fb3fafc5f2a4 100644
--- a/chrome/browser/sync_file_system/drive_backend/metadata_database.h
+++ b/chrome/browser/sync_file_system/drive_backend/metadata_database.h
@@ -343,6 +343,11 @@ class MetadataDatabase {
   // Sets |app_ids| to a list of all registered app ids.
   void GetRegisteredAppIDs(std::vector<std::string>* app_ids);
 
+  // Clears dirty flag of trackers that can be cleared without external
+  // interactien.
+  void SweepDirtyTrackers(const std::vector<std::string>& file_ids,
+                          const SyncStatusCallback& callback);
+
  private:
   friend class MetadataDatabaseTest;
   struct CreateParam;
@@ -402,6 +407,7 @@ class MetadataDatabase {
                                   const std::string& file_id);
 
   void DetachFromSequence();
+  bool CanClearDirty(const FileTracker& tracker);
 
   scoped_refptr<base::SequencedTaskRunner> worker_task_runner_;
   base::FilePath database_path_;