Add a force pipelining option to load flags.

net/http/http_stream_factory_impl_request.h

Index: net/http/http_stream_factory_impl_request.h
diff --git a/net/http/http_stream_factory_impl_request.h b/net/http/http_stream_factory_impl_request.h
index ffa3a4506098b3542f23537b629d4f15e28cb8dc..d258799ab5689b4bf45eb1fe04cd7c129ba11e9e 100644
--- a/net/http/http_stream_factory_impl_request.h
+++ b/net/http/http_stream_factory_impl_request.h
@@ -34,7 +34,8 @@ class HttpStreamFactoryImpl::Request : public HttpStreamRequest {
   // Called when the Job determines the appropriate |http_pipelining_key| for
   // the Request. Registers this Request with the factory, so that if an
   // existing pipeline becomes available, this Request can be late bound to it.
-  void SetHttpPipeliningKey(const HostPortPair& http_pipelining_key);
+  // Returns true if this is this key was new to the factory.
+  bool SetHttpPipeliningKey(const HttpPipelinedHost::Key& http_pipelining_key);
 
   // Attaches |job| to this request. Does not mean that Request will use |job|,
   // but Request will own |job|.
@@ -113,7 +114,7 @@ class HttpStreamFactoryImpl::Request : public HttpStreamRequest {
   scoped_ptr<Job> bound_job_;
   std::set<HttpStreamFactoryImpl::Job*> jobs_;
   scoped_ptr<const HostPortProxyPair> spdy_session_key_;
-  scoped_ptr<const HostPortPair> http_pipelining_key_;
+  scoped_ptr<const HttpPipelinedHost::Key> http_pipelining_key_;
 
   bool completed_;
   bool was_npn_negotiated_;