Boost remote animation process earlier

Previously, the animating state of remote process is updated when the
transition is ready, which means that it waits until the opening apps
are drawn. Now it updates the state when requesting transition.

This can benefit 2 cases:
1. Launch apps from home
It can avoid flipping process scheduling group of home with
top->foreground->top during transition. Because the sequence is:
"home is top activity" -> "the launching app becomes top activity"
-> "home is running transition animation".

2. Swipe up to return to home
The activity lifecycle callbacks and the first frame of home can
almost always run on big cores.

Fix: 300535986
Test: atest TransitionTests#testRunningRemoteTransition
Change-Id: I80bc98468a3bd0011efa996bf7a54a1e7ae7059b