Allow proxying plaintext websockets over http/2 proxy

net/http/http_stream_factory_impl_job.cc

Index: net/http/http_stream_factory_impl_job.cc
diff --git a/net/http/http_stream_factory_impl_job.cc b/net/http/http_stream_factory_impl_job.cc
index 2cd3bcbe0b6c7cf73b0129896405537a9a92cfcb..382e79c9ed30b5f7c6d43c95b780cd3ab2d44527 100644
--- a/net/http/http_stream_factory_impl_job.cc
+++ b/net/http/http_stream_factory_impl_job.cc
@@ -1164,8 +1164,17 @@ int HttpStreamFactoryImpl::Job::DoCreateStream() {
   if (connection_->socket() && !connection_->is_reused())
     SetSocketMotivation();
 
-  if (!using_spdy_) {
+  if (!using_spdy_)
     DCHECK(!IsSpdyAlternative());
+
+  if (!using_spdy_ ||
+      // While websockets over HTTP/2 are not supported, it is still valid to

[Bence, 2017/01/24 22:54:19]

Please move this comment one line above (or below) so as not to cut into the
multi-line condition.

[baranovich, 2017/01/25 09:10:51]

Done.

+      // have websockets tunneled through HTTP/2 proxy (via CONNECT). If
+      // websockets are secure (wss://), ProxyClientSocket with established
+      // tunnel is wrapped with yet another socket (SSLClientSocket), and
+      // |using_spdy_| will be false, but for ws: scheme, ProxyClientSocket is
+      // not wrapped into anything.
+      (using_spdy_ && proxy_info_.is_https() && delegate_->for_websockets())) {
     // We may get ftp scheme when fetching ftp resources through proxy.
     bool using_proxy = (proxy_info_.is_http() || proxy_info_.is_https()) &&
                        (request_info_.url.SchemeIs(url::kHttpScheme) ||