Post clean up starting window related data.

When Core request to add another starting window to the same task, shell
will remove previous starting window if any. Also clear related data
so the mStartingData won't be reused to create another starting window.

Bug: 341054451
Test: atest ActivityRecordTests
Change-Id: Ibc507a9cf841d620c3c53a57da4becdd4ef1a491
2 files changed