Adjust update interval when expiring location requests.

This is a more complete solution for this issue that disables
location providers when expiring their last request *and* adjusts
update intervals when expiring any request. This should help
further limit battery drain when a high-frequency-update app
exits, as it allows the system to throttle the update interval
back down to something appropriate for the remaining listeners.

Bug: 7611837
Change-Id: I88b419c92940b7e536d48b26e5fc0f72f3c9e73d