Merge "Track frozen duration in procstats." into udc-qpr-dev am: 3f6427fc am: 864cc021

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24471278



Change-Id: I2b2ba3c8f979c92505a93e3a87d681e2ce04da79
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>