Remove SpdyStream::GetSSLCertRequestInfo.

SPDY's multiplexing is incompatible with the renego + client auth hack. The old
implementation also assumed that the SpdyStream was still alive which isn't
true. We could attempt save a copy of it, but that doesn't resolve the
fundamental incompatibility of the hack. Instead
https://codereview.chromium.org/1131763002/ disables renegotiation, so this
codepath should be impossible.

BUG=462283

Review URL: https://codereview.chromium.org/1128873008

Cr-Commit-Position: refs/heads/master@{#329493}
5 files changed