DismissKeyguardUtil tweaks.

Add activity so it can be prelaunched and thus work on ICS+.
Change makefile to build it in data app.
Add ability to AppSetup to skip uninstalling packages, so DismissKeyguardUtil
can be left installed on device.

Bug 7697481

Change-Id: I464b21a6961df029e3ea30037bd6902ea2bbe3ba
7 files changed