Do not turn off theater mode on power key

Theater mode will now be turned off by users from QSS.
This removes functionality in PhoneWindowManager that turns off theater
mode on power key press.

Bug: 294343851

Change-Id: Iac23d2e643c900efd1f445d0d3b8f72728bb172b
(cherry picked from commit 683e0a09477554ca67b74f83ac06d7333fcf4fba)
(cherry picked from commit 285fea9c10371d5ab3759c024a651f392233e54c)