SysUI Tests: Make tests not break SysUI

Now you can run the tests without getting the blank broken sysui.
The tests instrument themselves so they include all of the source
they need to run rather than piggybacking on the sysui process.

A couple of changes were needed for this.  The xml files cannot
reference com.android.systemui, instead they must use res-auto.
The tests can no longer make privileged calls, so some restructuring
to avoid those calls was needed.

Bug: 18222975
Change-Id: I67b794af854f1420583d48960bd6e52ca753b56d