Revert "Fix uninitialized mScreenOn boolean in Clock"

This reverts commit 03bd8f098972d4395abb2ee03b1e10fc8f933a20.

Change-Id: Ib52e5412613abaf146c15ab6b9543e744900afcf
Merge "Revert "Fix uninitialized mScreenOn boolean in Clock"" into pac-4.4