Add proto dump flag to services (2/2)

Adds new PROTO flag which requests services to dump sections in proto format. Modifies PriorityDumper helper class to parse proto arguments and set asProto flags. Registers WM and AM with proto dump supprt.

Bug: 67716082

Test: frameworks/base/services/tests/runtests.py -e class "com.android.server.utils.PriorityDumpTest"
Test: adb bugreport ~/tmp/bug.zip
Test: adb shell dumpsys window --proto
Test: adb shell dumpsys activity --proto

Change-Id: Icfc6857c8a9340110a43343734a27e48d0b5a229