PlzNavigate: fix timing issue in app window creation

extensions/browser/api/app_window/app_window_api.cc

 // Copyright (c) 2012 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/browser/api/app_window/app_window_api.h"
 
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_types.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/common/content_switches.h"
 #include "content/public/common/url_constants.h"
 #include "extensions/browser/app_window/app_window.h"
 #include "extensions/browser/app_window/app_window_client.h"
 #include "extensions/browser/app_window/app_window_contents.h"
 #include "extensions/browser/app_window/app_window_registry.h"
 #include "extensions/browser/app_window/native_app_window.h"
 #include "extensions/browser/extensions_browser_client.h"
 #include "extensions/common/api/app_window.h"
 #include "extensions/common/features/simple_feature.h"
 #include "extensions/common/image_util.h"
@@ skipping 333 matching lines @@
   SetResult(result);
 
   if (AppWindowRegistry::Get(browser_context())
           ->HadDevToolsAttached(app_window->web_contents())) {
     AppWindowClient::Get()->OpenDevToolsWindow(
         app_window->web_contents(),
         base::Bind(&AppWindowCreateFunction::SendResponse, this, true));
     return true;
   }
 
+  // PlzNavigate: delay sending the response until the newly created window has
+  // been told to navigate, and blink has been correctly initialized in the
+  // renderer.
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          ::switches::kEnableBrowserSideNavigation)) {
+    app_window->SetOnFirstCommitCallback(
+        base::Bind(&AppWindowCreateFunction::SendResponse, this, true));
+    return true;
+  }
+
   SendResponse(true);
   app_window->WindowEventsReady();
 
   return true;
 }
 
 bool AppWindowCreateFunction::GetBoundsSpec(
     const app_window::CreateWindowOptions& options,
     AppWindow::CreateParams* params,
     std::string* error) {
@@ skipping 168 matching lines @@
 
   if (options.frame->as_frame_options->inactive_color.get()) {
     error_ = app_window_constants::kInactiveColorWithoutColor;
     return false;
   }
 
   return true;
 }
 
 }  // namespace extensions