Merge "Revert "Reapply "Add support for product-specific build flags""" into main am: 5f24ce61

Original change: https://android-review.googlesource.com/c/platform/build/+/2818085



Change-Id: Iaaa94d9613c29e8f88a8a56e7a041e1b19935691
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>