[automerger skipped] Add developer option for back animation DO NOT MERGE am:...

[automerger skipped] Add developer option for back animation DO NOT MERGE am: 94f506aa am: 3151a65e am: 45a141d5 am: cfe055c6 -s ours

am skip reason: subject contains skip directive

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17619727



Change-Id: I24418747ccb8dcfae61d6e9ac8cb6a5ea61a98b9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>