Merge "build system to create flag storage files per partition" into main am: 27cf1a5c

Original change: https://android-review.googlesource.com/c/platform/build/+/2908579



Change-Id: Ie53a53ab77c5318209faa55e68c2c94f2626abaa
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>