[Extensions] Make port creation synchronous in unload handlers

extensions/renderer/extension_frame_helper.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/renderer/extension_frame_helper.h"
 
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/string_util.h"
 #include "base/timer/elapsed_timer.h"
 #include "content/public/renderer/render_frame.h"
@@ skipping 223 matching lines @@
   pending_port_requests_[port_request_id] =
       base::MakeUnique<PendingPortRequest>(PortType::NATIVE_APP, callback);
   {
     SCOPED_UMA_HISTOGRAM_TIMER(
         "Extensions.Messaging.GetPortIdSyncTime.NativeApp");
     render_frame()->Send(new ExtensionHostMsg_OpenChannelToNativeApp(
         render_frame()->GetRoutingID(), native_app_name, port_request_id));
   }
 }
 
+int ExtensionFrameHelper::RequestSyncPortId(
+    const ExtensionMsg_ExternalConnectionInfo& info,
+    const std::string& channel_name,
+    bool include_tls_channel_id) {
+  int port_id = 0;
+  render_frame()->Send(new ExtensionHostMsg_OpenChannelToExtensionSync(
+      render_frame()->GetRoutingID(), info, channel_name,
+      include_tls_channel_id, &port_id));
+  return port_id;
+}
+
 void ExtensionFrameHelper::DidMatchCSS(
     const blink::WebVector<blink::WebString>& newly_matching_selectors,
     const blink::WebVector<blink::WebString>& stopped_matching_selectors) {
   extension_dispatcher_->content_watcher()->DidMatchCSS(
       render_frame()->GetWebFrame(), newly_matching_selectors,
       stopped_matching_selectors);
 }
 
 void ExtensionFrameHelper::DidStartProvisionalLoad() {
   if (!delayed_main_world_script_initialization_)
@@ skipping 155 matching lines @@
   }
   request.callback.Run(port_id);
   pending_port_requests_.erase(iter);
 }
 
 void ExtensionFrameHelper::OnDestruct() {
   delete this;
 }
 
 }  // namespace extensions