Make test transition ready by sync engine

If Transition's onTransactionReady is invoked directly, it won't
remove the sync set from BLASTSyncEngine#mActiveSyncs. Then if
timeout happens on a finished sync set, it won't be skipped that
leads to throw exception "Trying to move non-collecting transition".

This makes the tests closer to real process.

Fix: 397533893
Flag: EXEMPT TEST_ONLY
Test: atest DisplayContentTests#testRespectNonTopVisibleFixedOrientation
            TransitionTests
Change-Id: I3cf2bba1c08d2807d1d13fca6f9ac536a718dd54