Add embedder-specific headers to HTTP CONNECT tunnel request

net/http/http_proxy_client_socket_pool.cc

Index: net/http/http_proxy_client_socket_pool.cc
diff --git a/net/http/http_proxy_client_socket_pool.cc b/net/http/http_proxy_client_socket_pool.cc
index 829a5e78314968bca7b6acce7b9f6fd3c7215482..9f3b4b663ace5f1eceb5931afb4431620e5709ba 100644
--- a/net/http/http_proxy_client_socket_pool.cc
+++ b/net/http/http_proxy_client_socket_pool.cc
@@ -6,6 +6,7 @@
 
 #include <algorithm>
 
+#include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/time/time.h"
 #include "base/values.h"
@@ -37,7 +38,9 @@ HttpProxySocketParams::HttpProxySocketParams(
     HttpAuthCache* http_auth_cache,
     HttpAuthHandlerFactory* http_auth_handler_factory,
     SpdySessionPool* spdy_session_pool,
-    bool tunnel)
+    bool tunnel,
+    const base::Callback<void(const HostPortPair&, HttpRequestHeaders*)>&
+        before_proxy_tunnel_connect_callback)
     : transport_params_(transport_params),
       ssl_params_(ssl_params),
       spdy_session_pool_(spdy_session_pool),
@@ -46,7 +49,9 @@ HttpProxySocketParams::HttpProxySocketParams(
       endpoint_(endpoint),
       http_auth_cache_(tunnel ? http_auth_cache : NULL),
       http_auth_handler_factory_(tunnel ? http_auth_handler_factory : NULL),
-      tunnel_(tunnel) {
+      tunnel_(tunnel),
+      before_proxy_tunnel_request_callback_(
+          before_proxy_tunnel_connect_callback) {
   DCHECK((transport_params.get() == NULL && ssl_params.get() != NULL) ||
          (transport_params.get() != NULL && ssl_params.get() == NULL));
   if (transport_params_.get()) {
@@ -291,6 +296,7 @@ int HttpProxyConnectJob::DoHttpProxyConnect() {
                                 params_->tunnel(),
                                 using_spdy_,
                                 protocol_negotiated_,
+                                params_->before_proxy_tunnel_request_callback(),
                                 params_->ssl_params().get() != NULL));
   return transport_socket_->Connect(callback_);
 }
@@ -372,10 +378,14 @@ HttpProxyConnectJobFactory::HttpProxyConnectJobFactory(
     TransportClientSocketPool* transport_pool,
     SSLClientSocketPool* ssl_pool,
     HostResolver* host_resolver,
+    base::Callback<void(const HostPortPair&, HttpRequestHeaders*)>
+        before_proxy_tunnel_request_callback,
     NetLog* net_log)
     : transport_pool_(transport_pool),
       ssl_pool_(ssl_pool),
       host_resolver_(host_resolver),
+      before_proxy_tunnel_request_callback_(
+          before_proxy_tunnel_request_callback),
       net_log_(net_log) {
   base::TimeDelta max_pool_timeout = base::TimeDelta();
 
@@ -391,6 +401,10 @@ HttpProxyConnectJobFactory::HttpProxyConnectJobFactory(
     base::TimeDelta::FromSeconds(kHttpProxyConnectJobTimeoutInSeconds);
 }
 
+HttpProxyClientSocketPool::
+HttpProxyConnectJobFactory::~HttpProxyConnectJobFactory() {
+}
+
 
 scoped_ptr<ConnectJob>
 HttpProxyClientSocketPool::HttpProxyConnectJobFactory::NewConnectJob(
@@ -421,6 +435,8 @@ HttpProxyClientSocketPool::HttpProxyClientSocketPool(
     HostResolver* host_resolver,
     TransportClientSocketPool* transport_pool,
     SSLClientSocketPool* ssl_pool,
+    const base::Callback<void(const HostPortPair&, HttpRequestHeaders*)>&
+        before_proxy_tunnel_request_callback,
     NetLog* net_log)
     : transport_pool_(transport_pool),
       ssl_pool_(ssl_pool),
@@ -430,6 +446,7 @@ HttpProxyClientSocketPool::HttpProxyClientSocketPool(
             new HttpProxyConnectJobFactory(transport_pool,
                                            ssl_pool,
                                            host_resolver,
+                                           before_proxy_tunnel_request_callback,
                                            net_log)) {
   // We should always have a |transport_pool_| except in unit tests.
   if (transport_pool_)