libprocessgroup: implement task profile validity checks am: 4a8c1461 am: 50395c74

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/22919937



Change-Id: I7787dfd839e2c1f39bf42d95ce767c78388e923c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>