Disambiguate apps that share uid for job/bucket purposes

Specifically, we no longer update our cached standby state bookkeeping for
*all* apps under that uid when a standby policy change notification comes
in.  We weren't properly handling shared uids; and now we are.

Change-Id: I4bda6233ebeff259cc63bdb8a4febbc83f2e1043
Fixes: 73663980
Test: atest CtsJobSchedulerTestCases