Fix background request throttling + jitter calculation

Prevent applications from bypassing background location throttling by
adding/removing requests. This allows provider managers to delay
requests in the event the interval has decreased so that power can be
saved. Clients that target S and above may now receive historical
locations in exchange, so that they are not losing locations overall.
Locationp providers can optionally implement delays themselves in the
event of an interval increase.

Also updates jitter calculation to be a capped percentage of the
request interval, rather than a flat cap.

Bug: 73144566
Test: manual + presubmits
Change-Id: I243e813f0c0c504850e2a3e777787f49fc6f7a57