Merge "Prevent exfiltration of system files via avatar picker." into sc-dev am: 43e0f944

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19748987



Change-Id: I53cffafb85ff996ff02a0e404d965367bacc039c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>