Fixed a NP when replying to a message

The visbilityChanged listener is only set up later,
so we'll have to add a nullcheck for it.

Change-Id: I1f5843f02fd9c8fc20e26f1de47911e5eb533471
Fixes: 73758799
Test: runtest -x packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/RemoteInputViewTest.java
2 files changed