[Sync] Implementation of model association for passwords using sync API

sync/api/sync_error.h

Index: sync/api/sync_error.h
diff --git a/sync/api/sync_error.h b/sync/api/sync_error.h
index 306ed83fc72421b1bef249dfe04d6b2d4cc9b7ac..20f3c90df7a58e2db8001e4e48d91a988c48a826 100644
--- a/sync/api/sync_error.h
+++ b/sync/api/sync_error.h
@@ -74,6 +74,9 @@ class SYNC_EXPORT SyncError {
 
   // Returns empty string is IsSet() is false.
   std::string ToString() const;
+
+  // Logs the data load failures for the |model_type| in UMA.
+  static void LogDataLoadFailure(ModelType model_type);

[Ilya Sherman, 2013/12/05 07:01:54]

nit: Please leave a blank line after this one.

  private:
   // Print error information to log.
   void PrintLogError() const;