Avoid starting home that targeted before Q on secondary display

Some launchers don't explicitly request for single instance.
Since these launchers could be launched on secondary displays
and having multiple instances at the same time, the applications
may not work properly if they were implemented based on a single
display/instance assumption.

Bug: 111363427
Test: atest ActivityStackSupervisorTests
Test: atest ActivityManagerMultiDisplayTests

Change-Id: Ib1de00c6bca89c0e588dd2a5883bceb8887b3f76