Revert "Revert "DispSync: Always resync after inactivity""

This reverts commit 67264e930992e43ef3351b04692d4ca59cbb01ad.

We've fixed the kernel issues this exposed.

bug 28198793

Change-Id: Ie895cc0a815094cce4bee3b2bf45800ee1e2fdc3
7 files changed