Merge "Document that ro.dalvik.vm.enable_uffd_gc has a limited lifetime." into main am: a8bb538d

Original change: https://android-review.googlesource.com/c/platform/build/+/3088506



Change-Id: Ie5b266bcce1dfe003d477e4626075483dd6bcbce
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>