Fixed an issue where GONE Views would show during transitions

Because we're clipping children and MotionLayout doesn't hide them
when collapsed, views could flicker onto the screen

Test: add media notification, swipe down to shade and back, observe no flickering
Bug: 154137987
Change-Id: Ida591706e779215e13c6d3047be7e3b5318b4d19
3 files changed