Add an unstable fallback for the gnss/fused location provider overlay

Keeps track of the number of times a given service has died in the last minute, and if a service has died ten times, mark it as unstable and always prefer non-unstable services.

Flag: android.location.flags.service_watcher_unstable_fallback
Bug: 402997842
Test: Manual
Change-Id: I8ad3fb6fb5497b2d828b10269afb9c8e0d215a0a