HttpStreamFactoryImpl::JobController should filter out AlternativeServiceInfo that does not contain a client supported QUIC version.
When HttpServerProperties stores AlternativeServiceInfo which contains a list of advertised QUIC versions by the server, there is at least one QUIC version supported by Chrome. This version list is persisted to disk and reload to memory when Chrome restarts. If an update/restart happens, and Chrome happens to migrate supporting a QUIC_VERSION_A to QUIC_VERSION_B. It could be possible that the version list cached in HttpServerProperties doesn't contain VERSION_B but VERSION_A. We should not try creating alternative job for those AlternativeServiceInfo.
Comment 1 by bugdroid1@chromium.org
, Jul 5 2017