Lazy RemoveCanonicalHost().

Call RemoveCanonicalHost() when the alternative service is found to be broken
upon lookup, instead of when the alternative service is first marked broken.
This will allow SetBrokenAlternateProtocol to take an alternative service
instead of an origin.

BUG=392576

Review URL: https://codereview.chromium.org/1014303002

Cr-Commit-Position: refs/heads/master@{#321466}
1 file changed