SPDY - disable spdy/2.1 (flow control) by default

net/http/http_stream_factory.cc

Index: net/http/http_stream_factory.cc
===================================================================
--- net/http/http_stream_factory.cc	(revision 124201)
+++ net/http/http_stream_factory.cc	(working copy)
@@ -10,7 +10,6 @@
 #include "googleurl/src/gurl.h"
 #include "net/base/host_mapping_rules.h"
 #include "net/base/host_port_pair.h"
-#include "net/http/http_server_properties.h"
 
 namespace net {
 
@@ -39,6 +38,8 @@
 uint16 HttpStreamFactory::testing_fixed_http_port_ = 0;
 // static
 uint16 HttpStreamFactory::testing_fixed_https_port_ = 0;
+// static
+AlternateProtocol HttpStreamFactory::supported_spdy_version_ = NPN_SPDY_2;
 
 HttpStreamFactory::~HttpStreamFactory() {}
 
@@ -56,6 +57,7 @@
   force_spdy_always_ = false;
   forced_spdy_exclusions_ = NULL;
   ignore_certificate_errors_ = false;
+  supported_spdy_version_ = NPN_SPDY_2;
 }
 
 void HttpStreamFactory::ProcessAlternateProtocol(
@@ -87,7 +89,8 @@
       protocol = static_cast<AlternateProtocol>(i);
   }
 
-  if (protocol == ALTERNATE_PROTOCOL_BROKEN) {
+  if (protocol != supported_spdy_version_ ||

[Ryan Hamilton, 2012/03/01 18:56:20]

As we discussed offline, this approach only allows us to speak a single version
at a time.  It would prevent us from speaking 2 or 2.1 depending on what the
server advertises.

We discussed having HttpStreamFactory maintain an array of booleans indexed by
NPN_foo.  If array[NPN_foo] is true, then that version is enabled, otherwise it
is not.  This would be simple, efficient, and flexible.

[willchan no longer on Chromium, 2012/03/01 18:57:54]

Whew, good catch! I didn't notice this. This is important, since most other SPDY
websites won't advertise 2.1.

+      protocol == ALTERNATE_PROTOCOL_BROKEN) {
     // Currently, we only recognize the npn-spdy protocol.
     DLOG(WARNING) << kAlternateProtocolHeader
                   << " header has unrecognized protocol: "