Drop TaskFragment Transitions if behind starting window

Animation is not needed if all the TF changes are behind the starting
window. Without this change, the transition is merged into the remote
transition, causing the latter being canceled.

Bug: 328775431
Test: Manually launch Settings app from Quick Settings
Flag: EXEMPT bugfix
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:431087e3b66e4e1da86d5d36a556fcc5e55332d4)
Merged-In: I7c46209322c19763048ebfee91a633a8168cd81a
Change-Id: I7c46209322c19763048ebfee91a633a8168cd81a