Re-arrange OOM killer to account for SERVICE_ADJ and PREVIOUS_APP_ADJ in slots

See: http://forum.xda-developers.com/showpost.php?p=50044022&postcount=1500

Conflicts:
	services/java/com/android/server/am/ProcessList.java

(cherry picked from commit 76f0df0b5c8081d4d8ac1d4521e074be640f7369)

Change-Id: I93faaa361ab7e3ba226d9f9ebd3cc4cd6ba733db