Refactor browser side navigator.connect code to not use MessagePortService.

content/browser/navigator_connect/service_port_service_impl.cc

Index: content/browser/navigator_connect/service_port_service_impl.cc
diff --git a/content/browser/navigator_connect/service_port_service_impl.cc b/content/browser/navigator_connect/service_port_service_impl.cc
index 432f57fb76a1dac100ef974b8e617472ed83af5d..c8847a7f5b4413156a1d1f859ba395051f97a3c9 100644
--- a/content/browser/navigator_connect/service_port_service_impl.cc
+++ b/content/browser/navigator_connect/service_port_service_impl.cc
@@ -110,10 +110,9 @@ void ServicePortServiceImpl::PostMessage(
     mps->QueueMessages(port.id);
   }
 
-  // Second, pass of the actual to MessagePortService now ServicePort instances
-  // are still backed by MessagePort.
-  mps->PostMessage(port_id, MessagePortMessage(message.To<base::string16>()),
-                   transferred_ports);
+  navigator_connect_context_->PostMessage(
+      port_id, MessagePortMessage(message.To<base::string16>()),
+      transferred_ports);
 }
 
 void ServicePortServiceImpl::ClosePort(int32_t port_id) {