First version of HPJs.

This is the base implementation for HPJs. It allows scheduling and
running of HPJs with their own quota. Quota is regained when previous
sessions expire and when certain events take place.

A few things still aren't implemented yet. They'll be done in a separate
CL:
1. Free temp-allowlist jobs
2. Dedicated JobServiceContexts for HPJs
3. Additional quota for system-critical roles

Bug: 171305774
Test: atest --rerun-until-failure 5 com.android.server.job.controllers.QuotaControllerTest
Test: atest CtsJobSchedulerTestCases
Change-Id: I4b704cb0b406769f6de8b60bf762dd1f4eb10c68