Merge changes from topic "readonly_generic_ramdisk" am: 696882455b am: 3401909e7c

Original change: https://android-review.googlesource.com/c/platform/system/core/+/1519823

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I696a169b18eb038958dafa45f63cd9a5528456c0