Add quality to LocationRequest/ProviderRequest

Expose quality APIs publically after refactoring them to match external
usage of quality constants. Removes list of location requests from
provider request, as there is no client that really uses this, and it
feels like too much information to give to providers.

Bug: 168624248
Test: presubmits
Change-Id: Icf8a9f6096da0071d97190d3f7196948492e52a1