Use userfaultfd in COPY mode even when minor-fault available am: 41af30d7d4 am: 2d04f326ce am: 3dfc5d3053

Original change: https://android-review.googlesource.com/c/platform/art/+/2393852

Change-Id: I4d3d8df1491ba5578a8f45dd23c8c401e8030182
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>