Update the default location mode for Battery Saver in order to get

droidfood test coverage on the intended change.

This value is also protected by flags so it can be set to the previous
value while we run requested population experiments. Power tests show
that this change causes a < 1% change in days of use (see b/178902585).

Bug: 184875711
Test: Manual
Change-Id: Ied13dc79b0dca655dea05ad61f0b54f81290673c