Merge "[flexiglass] Use transitionState instead of currentScene." into udc-qpr-dev am: 5fbbe4489d

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24329708

Change-Id: Ie50a016eea8adbf809e7623836f0c72f0a937f7b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>