Ensure PiP window visible after fold/unfold device

We used to do only PipTaskOrganizer#scheduleResizePip without commiting
PipTaskOrganizer#scheduleFinishResizePip upon display change.

Bug: 241961056
Test: Enter PiP in unfolded state then fold the device
Test: atest WMShellUnitTests:PipControllerTest
Change-Id: I1c72c5e6016cd19017b43a8df583e730f15619a1