Merge "Build system_ext build.prop with Soong" into main am: 90531960 am: ae323c17

Original change: https://android-review.googlesource.com/c/platform/build/+/3204711



Change-Id: I05c78eb8b1ece769b66573ae3e25fdd1c1d6cb63
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>