Verify IPv6 name servers in the IPConfig obtained from RDNSS

BUG=chromium:398047
TEST=Run network_Ipv6SimpleNegotiation test
CQ-DEPEND=CL:212073

Change-Id: Id3e522caa9fd15038b4c2f68fc86a2d628a85049
Reviewed-on: https://chromium-review.googlesource.com/212121
Reviewed-by: Paul Stewart <pstew@chromium.org>
Tested-by: Peter Qiu <zqiu@chromium.org>
Commit-Queue: Peter Qiu <zqiu@chromium.org>
2 files changed