Fix the issue malformed SQL statement was provided during db

sanitization.

Bug: 147114476
Change-Id: I34459267cfacb168ec520856e90e5da0b83728f0
Test:
1. follow the verification step in ag/9891836
2. add the following line in Launcher#onResume
LauncherSettings.Settings.call(getContentResolver(),
        LauncherSettings.Settings.METHOD_RESTORE_BACKUP_TABLE);
3. build & flash on the device
4. verify sanitizeDb success without error message