Pass correct realCallingUid to startActivity() if provided

by PendingIntentRecord#sendInner()

Previously we'd ignore realCallingPid and realCallingUid that
PendingIntentRecord#sendInner() provided to startActivityInPackage().
Now we correctly pass it on, preserving past behaviour if none
provided.
Also, PendingIntentRecord#sendInner() now passes that information
to startActivitiesInPackage() as well.

Bug: 123013720
Test: atest WmTests:ActivityStarterTests
Change-Id: Ifdfee0fb2dda2377f6afa24440a4dd15f5586f4d