Merge "SilkFX: add gainmap metadata testing" into udc-dev am: f5f517a2 am: 87d76fcb am: f962a1bd am: 36795ce1

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22870336



Change-Id: I9f9169e89d3f4f29a324ca16cfd0052edd62fb65
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>