Merge "Revert "Introduce Windowless starting window."" into udc-dev am: f515de95

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21590159



Change-Id: Id4312eb4393f6c6150583f815ef570ef85747a0a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>