Remove redundant MediaRouter2Manager fields

    private static MediaRouter2Manager sInstance;

    private final MediaSessionManager mMediaSessionManager;

    final String mPackageName;

    private final Context mContext;

    private final Client mClient;

    private final IMediaRouterService mMediaRouterService;

    private final AtomicInteger mScanRequestCount = new AtomicInteger(/* initialValue= */ 0);

    final Handler mHandler;

    }

    private MediaRouter2Manager(Context context) {

        mContext = context.getApplicationContext();

        mMediaRouterService = IMediaRouterService.Stub.asInterface(

                ServiceManager.getService(Context.MEDIA_ROUTER_SERVICE));

        mMediaSessionManager = (MediaSessionManager) context

                .getSystemService(Context.MEDIA_SESSION_SERVICE);

        mPackageName = mContext.getPackageName();

        mHandler = new Handler(context.getMainLooper());

        mClient = new Client();

        try {

            mMediaRouterService.registerManager(mClient, mPackageName);

            mMediaRouterService.registerManager(mClient, context.getPackageName());

        } catch (RemoteException ex) {

            throw ex.rethrowFromSystemServer();

        }