Dismisses system overlays for Home intent.

Test: Used Facebook chatheads (not system bubble).
Before the change, Home gesture didn't work. After
the change, it does work :)
Bug: 146593239

Merged-In: Ib9c85de2f83f99d1ef53fb17fde5d0b3c514849a
Change-Id: I19d91aaed19ccaec68478e364ce6b80049d49a98
4 files changed