Add power button cooldown after emergency gesture is triggered.

Bug: 195782998
Test: unit tests, manual test on device
Change-Id: I80dbfd5e297af6e62ecbd6593dd63686c1b7ac1c
Merged-In: I80dbfd5e297af6e62ecbd6593dd63686c1b7ac1c
(cherry picked from commit c22b2a9520ac6a1820df1599d61e98802278f240)
4 files changed