Cleanup some obsolete TODOs and unused code.

        mHandlerThread.start();

        Watchdog.getInstance().addThread(getHandler(), HANDLER_THREAD_TIMEOUT_DURATION_MILLIS);

        // TODO: Make sure to register these call backs when a new user is

        // added too.

        SessionCallback sessionCallback = new SessionCallback();

        for (UserInfo userInfo : UserManager.get(mContext).getUsers(true)) {

            registerUserCallbacks(userInfo.getUserHandle());

        }

            return;

        }

        // TODO: Reuse the same SessionCallback and broadcast receiver

        // instances, rather than creating new instances for each user.

        context.getPackageManager().getPackageInstaller()

                .registerSessionCallback(new SessionCallback(), getHandler());