Switched ActivityRecord.service to ActivityTaskManagerService (5/n)

Objects that contain or represent activities like ActivityRecord can
no longer rely on ActivityManagerService as it is going to be in a
different package.

Test: Existing tests pass
Test: go/wm-smoke-auto
Bug: 80414790
Change-Id: I7eabc9b80e494367d79ff7452c88ba82ff216bcd