loadUnbadgedItemIcon doesn't crash from getUserIcon

AppicationPackageManager.loadUnbadgedItemIcon would call
UserManager.getUserIcon if the icon was supposed to represent
switching to another the parent user (from a work profile).
However, that call requires extra permissions which may not be
available, which would cause a crash. The work profile doesn't
generally have permission to see the parent's icon, so rather
than showing the actual icon, a generic user icon is shown instead.

Bug: 134177607
Test: Manual confirmation: create a work profile and try to share a
picture (from Photos) to the personal profile.

Change-Id: Id79ca50b8e0a26593addbacf1a0ea709a2bc4da2