Do not re-add alternate protocol in SetBrokenAlternateProtocol.

Do not re-add alternate protocol from canonical host to origin in
HttpServerPropertiesImpl::SetBrokenAlternateProtocol(), because brokenness is
recorded independently of the alternate protocol mapping.  I have overlooked
this detail in
https://crrev.com/997953003/diff/80001/net/http/http_server_properties_impl.cc.

BUG=392576

Review URL: https://codereview.chromium.org/1011873002

Cr-Commit-Position: refs/heads/master@{#320897}
1 file changed