Makes captive portal server calculation in one place.

This also creates a hidden api for the captive portal server calculation
so that the Setup Wizard can use this as well.

bug:13246857
Change-Id: I4dfd0916df97cfce13252c7cc15f7bd05ed95f77
4 files changed
tree: c6088f60a56a7999a3e4c2ad7a231019edcf1a44
  1. core/
  2. services/
  3. tests/