Merge "Avoid locking in getCurrentUser when there is no user switch"

    private final Injector mInjector;

    private final Handler mHandler;

    // Holds the current foreground user's id

    // Holds the current foreground user's id. Use mLock when updating

    @GuardedBy("mLock")

    private int mCurrentUserId = UserHandle.USER_SYSTEM;

    // Holds the target user's id during a user switch

    private volatile int mCurrentUserId = UserHandle.USER_SYSTEM;

    // Holds the target user's id during a user switch. The value of mCurrentUserId will be updated

    // once target user goes into the foreground. Use mLock when updating

    @GuardedBy("mLock")

    private int mTargetUserId = UserHandle.USER_NULL;

    private volatile int mTargetUserId = UserHandle.USER_NULL;

    /**

     * Which users have been started, so are allowed to run code.

            Slog.w(TAG, msg);

            throw new SecurityException(msg);

        }

        // Optimization - if there is no pending user switch, return current id

        if (mTargetUserId == UserHandle.USER_NULL) {

            return getUserInfo(mCurrentUserId);

        }

        synchronized (mLock) {

            return getCurrentUserLocked();

        }