Add UpsideDownCake to aapt2 codenames and android.os.Build am: e422b7da01

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21423290

Change-Id: Ic408730f700e822eaa65c27ce867a0d657860c96
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>