Merge "Fix an issue which causes back key doesn't work"

    @Override

    public long interceptKeyBeforeDispatching(WindowState win, KeyEvent event, int policyFlags) {

        final long result = interceptKeyBeforeDispatchingInner(win, event, policyFlags);

        final int eventDisplayId = event.getDisplayId();

        if (result == 0 && !mPerDisplayFocusEnabled

                && event.getDisplayId() != mTopFocusedDisplayId) {

                && eventDisplayId != INVALID_DISPLAY && eventDisplayId != mTopFocusedDisplayId) {

            // Someone tries to send a key event to a display which doesn't have a focused window.

            // We drop the event here, or it will cause ANR.

            // TODO (b/121057974): The user may be confused about why the key doesn't work, so we

            // may need to deal with this problem.

            Slog.i(TAG, "Dropping this event targeting display #" + eventDisplayId

                    + " because the focus is on display #" + mTopFocusedDisplayId);

            return -1;

        }

        return result;

        if (mTopFocusedDisplayId != topFocusedDisplayId) {

            mTopFocusedDisplayId = topFocusedDisplayId;

            mWmService.mInputManager.setFocusedDisplay(topFocusedDisplayId);

            mWmService.mPolicy.setTopFocusedDisplay(topFocusedDisplayId);

            if (DEBUG_FOCUS_LIGHT) Slog.v(TAG_WM, "New topFocusedDisplayId="

                    + topFocusedDisplayId);

        }