GitLab

Host resolution will soon use per-context result tracking for the DoH
activation probes.  ContextHostResolver now owns a ResolveContext that
gets passed around in place of raw URLRequestContext to everywhere that
will need access to per-context data (probe results, DoH server
availability, server stats, etc).

Minor behavior change because JobKey now contains ResolveContext. This
means that requests from two different ContextHostResolvers will never
be merged into the same job, even if both are given the same
URLRequestContext. This shouldn't make a difference in practice because
we only create ContextHostResolvers 1:1 with URLRequestsContexts.

Bug: 1022059
Change-Id: Ia9b7bd4d1055630dbfdab627429638bb5f63eb8b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2002899
Commit-Queue: Eric Orth <ericorth@chromium.org>
Reviewed-by: Matt Menke <mmenke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#737509}