[MultiUser] Ensure sysyuig activities use user 0

Use packagename to determine if intent is in the same package and which
user should be used when launching the activity.

Bug: 229730387
Test: Manual on device
Change-Id: I1f1033dc875899567edd42a6fc67f9e6124fce73
Merged-In: I1f1033dc875899567edd42a6fc67f9e6124fce73
2 files changed