Write classes in runtime-generated app image. am: df68c0a6f0 am: 9ff3b10a03

Original change: https://android-review.googlesource.com/c/platform/art/+/2373830

Change-Id: Ia3cde5e33ce32292aa6d1879f6cb9a26ea45e29a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>