Merge "Improve docs for generated properties in PropertyMapper" am: 46a915f625 am: ef33f36050 am: 58b0f9d6b5 am: 1253941b56 am: c695becb54

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2165102

Change-Id: I494e512872b506b74b2dabfdf270640d1e8d6b4c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>