Camera: document multiResolution raw behavior am: 48e33c5c8b am: 87df804c0f

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/media/+/21549061

Change-Id: Ie69cd17de070db20875d054971d1c905d84fe8f2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>