Merge "Make setting the session token in MediaBrowserService synchronous" into lmp-mr1-dev

     * <p>

     * This should be called as soon as possible during the service's startup.

     * It may only be called once.

     *

     * @return The media session token, must not be null.

     */

    public void setSessionToken(final MediaSession.Token token) {

        if (token == null) {

            throw new IllegalArgumentException("Session token may not be null.");

        }

        mHandler.post(new Runnable() {

            @Override

            public void run() {

        if (mSession != null) {

            throw new IllegalStateException("The session token has already been set.");

        }

        mSession = token;

        mHandler.post(new Runnable() {

            @Override

            public void run() {

                for (IBinder key : mConnections.keySet()) {

                    ConnectionRecord connection = mConnections.get(key);

                    try {

                        connection.callbacks.onConnect(connection.root.getRootId(), mSession,

                        connection.callbacks.onConnect(connection.root.getRootId(), token,

                                connection.root.getExtras());

                    } catch (RemoteException e) {

                        Log.w(TAG, "Connection for " + connection.pkg + " is no longer valid.");