@Nullable
    @Override
    protected String getMessage() {
      if (myChangesCount < 0 || myConflictsCount < 0) return null;
      if (myChangesCount == 0 && myConflictsCount == 0) {
        return DiffBundle.message("merge.dialog.all.conflicts.resolved.message.text");
      }
      return DiffBundle.message("merge.differences.status.text", myChangesCount, myConflictsCount);
    }
@Nullable
    @Override
    protected String getMessage()