class TransportManager {

    @Deprecated
    @Nullable
    String selectTransport(String transportName) {
        synchronized (mTransportLock) {
            String prevTransport = mCurrentTransportName;
            mCurrentTransportName = transportName;
            return prevTransport;
        }
    }

      TransportManager(Context context, Set<ComponentName> whitelist, String selectedTransport);
    @VisibleForTesting  TransportManager(
            Context context,
            Set<ComponentName> whitelist,
            String selectedTransport,
            TransportClientManager transportClientManager);

}