Change the interface of GetAlternativeServicesFor, always return the best Alt-Svc entry.

net/quic/quic_stream_factory.cc

Index: net/quic/quic_stream_factory.cc
diff --git a/net/quic/quic_stream_factory.cc b/net/quic/quic_stream_factory.cc
index 2443381e3e4f20654a2aba7b839876f455279a42..043d4bcdc635e294fdafad668a4bca2afd87f845 100644
--- a/net/quic/quic_stream_factory.cc
+++ b/net/quic/quic_stream_factory.cc
@@ -25,7 +25,6 @@
 #include "net/cert/ct_verifier.h"
 #include "net/dns/host_resolver.h"
 #include "net/dns/single_request_host_resolver.h"
-#include "net/http/http_server_properties.h"
 #include "net/quic/crypto/channel_id_chromium.h"
 #include "net/quic/crypto/proof_verifier_chromium.h"
 #include "net/quic/crypto/properties_based_quic_server_info.h"
@@ -707,6 +706,21 @@ void QuicStreamFactory::set_quic_server_info_factory(
   quic_server_info_factory_.reset(quic_server_info_factory);
 }
 
+bool QuicStreamFactory::CanPool(HostPortPair host_port_pair,
+                                PrivacyMode privacy_mode,
+                                StringPiece origin_host) {
+  QuicServerId server_id(host_port_pair, privacy_mode);
+  if (!active_sessions_.empty()) {
+    SessionMap::iterator it = active_sessions_.find(server_id);
+    if (it != active_sessions_.end()) {
+      QuicChromiumClientSession* session = it->second;
+      if (session->CanPool(origin_host.as_string(), privacy_mode))
+        return true;
+    }
+  }

[Ryan Hamilton, 2015/12/18 17:52:51]

I'm a bit fan of early return instead of nesting, so I would do:

if (active_session_.empty()) 
  return false;
SessionMap::iterator it = active_sessions_.find(server_id);
if (it = active_sessions_.end())
  return false;
QuicChromiumClientSession* session = it->second;
return session->CanPool(origin_host.as_string(), privacy_mode);

(Actually, since I think find() will work with empty containers, I would
probably just omit the empty() check.)

+  return false;
+}
+
 int QuicStreamFactory::Create(const HostPortPair& host_port_pair,
                               PrivacyMode privacy_mode,
                               int cert_verify_flags,