Test Web Proxy Auto Config

Perform a DHCP negotiation where the server provides a Web Proxy
Auto Config option.  Test to make sure that the shill IPConfig
contains this value.

CQ-DEPEND=CL:60015
BUG=chromium:253915
TEST=This is a test.

Change-Id: Iae1d23f69e83c51b0cfc8afbc75cc3aec7fdd4dc
Reviewed-on: https://gerrit.chromium.org/gerrit/60020
Reviewed-by: Paul Stewart <pstew@chromium.org>
Tested-by: Paul Stewart <pstew@chromium.org>
Commit-Queue: Paul Stewart <pstew@chromium.org>
3 files changed