Avoid clearing rotation transform too early

This reduces flickering of display cutout when switching apps with
different orientations consecutively.

For example, when the display is updating to new rotation seamlessly
after returning from a landscape app to portrait home, immediately
launch the landscape app again. Some non activity windows may have
not drawn in new rotation, so their surfaces have unrotated transform
to preserve original appearance. If clearFixedRotationLaunchingApp is
called before the next transition completes, it may invoke
AsyncRotationController#completeAll to clear the transform, which
causes the windows to show old rotation appearance.

So skip the force finish for the collecting case and let the existing
AsyncRotationController handle the transform.

Bug: 403394916
Flag: EXEMPT bugfix
Test: TransitionTests#testFinishRotationControllerWithFixedRotation
Change-Id: Ib1418b9ee4e478f3f2f3e7fbae4f93c96a2ac3fc