Don't apply ForceHTTP11 for HTTP proxies.

We should be establishing HTTP connections to HTTP/1.1 proxies, so it's
weird to apply REQUIRES_HTTP_11 logic to them.

I'm planning on moving the force HTTP/1.1 bool into
HttpServerProperties::ServerInfo, to simplify the class. ServerInfo is,
however, keyed on HttpServerProperties rather than HostPortPair, and
using either an HTTPS or HTTP scheme in the HTTP proxy case when
calling MaybeForceHTTP11 seems weird.

Bug: 993801
Change-Id: I4237a28c6a16ea03fe9ad4f60657bd4c32a45b2f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1761635Reviewed-by: Bence Béky <bnc@chromium.org>
Commit-Queue: Matt Menke <mmenke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#688658}

net/http/http_stream_factory_job.cc

@@ -842,7 +842,7 @@ int HttpStreamFactory::Job::DoInitConnectionImpl() {
       session_->http_server_properties();
   if (http_server_properties) {
     http_server_properties->MaybeForceHTTP11(destination_, &server_ssl_config_);
-    if (proxy_info_.is_http() || proxy_info_.is_https()) {
+    if (proxy_info_.is_https()) {
       http_server_properties->MaybeForceHTTP11(
           proxy_info_.proxy_server().host_port_pair(), &proxy_ssl_config_);
     }