Put transition collect in scope of defer layout

Transition#collect will call BLASTSyncEngine.SyncGroup#addToSync,
which will request traversal. If it is called on a path which
will perform traversal at the end, the traversal request can
be consumed by that to avoid additional cost.

Bug: 260059642
Test: Enable shell transition.
      Launch an activity and check trace that there is no additional
      performSurfacePlacement on android.anim thread.
Change-Id: I6e58fc75f4f435ee730eff1bcc94848bdaedfbf0