update SystemUI's proguard.flags

Change-Id: I5aa73eddd3fea6cddeddaf94e202d8de870e7df5
Frameworks: privacy guard fix UI freeze

randomly sometimes the complete UI freezes when toggle
privacy guard. Move out the forcekill from syncronized to
fix it so that it kills the app when all threads are open
and they can react to the forcekill which cannot result then in unknown states

cheers

Change-Id: I81514dc5ca9149477ee747a7d90720b83f741baa