Merge "Add support for missing public / private key files for apexes." am:...

Merge "Add support for missing public / private key files for apexes." am: babb1337 am: d2344eea am: 595514bf am: 6ad39f61 am: b460a20d am: 7521b10d

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/2586953



Change-Id: Ib5194d085d6c5ebd3cdb9d4c8e98656fde2dfcc4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>