resourcemanager: define reclaim policy

Refactor the current design of the ResourceManagerService to
introduce Reclaim Policies.
This defines and implements the priority (oom score) of the process
as the default reclaim policy.
This change allows extending reclaim policies.

Bug: 294886363
Test: atest android.media.misc.cts.ResourceManagerTest
      atest android.media.misc.cts.ResourceManagerMultiTest
      /data/nativetest64/ResourceManagerService_test/ResourceManagerService_test
      /data/nativetest64/ResourceObserverService_test/ResourceObserverService_test
Change-Id: I0de0d86c08b1b148e2f813b884aa693b1643900c