Work on issue #25467052: System lagged out

Add a new mechanism where we retain previously used provided
processes in the "last activity" oom adj state for 20 seconds,
before allowing them to fall down to a regular cached process.
This should help reduce thrashing when something is acquiring
and releasing a provider repeatedly.

Change-Id: I889472de7bb4da574b46f07e36a99978813643cb
2 files changed