Fix the flakiness of MediaRouterUIBrowserTest.OpenDialogWithMediaRouterAction

chrome/browser/ui/views/media_router/media_router_ui_browsertest.cc

 // Copyright 2015 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 "base/bind.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/extensions/browser_action_test_util.h"
 #include "chrome/browser/media/router/media_router_ui_service.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
@@ skipping 51 matching lines @@
         BrowserView::GetBrowserViewForBrowser(browser())
             ->toolbar()
             ->app_menu_button();
 
     // When the Media Router Action executes, it opens a dialog with web
     // contents to chrome://media-router.
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE,
         base::Bind(&MediaRouterUIBrowserTest::ExecuteMediaRouterAction,
                    base::Unretained(this), app_menu_button));
+
+    base::RunLoop run_loop;
     app_menu_button->ShowMenu(false);
+    run_loop.RunUntilIdle();
 
     nav_observer.Wait();
     EXPECT_FALSE(app_menu_button->IsMenuShowing());
     ASSERT_EQ(chrome::kChromeUIMediaRouterURL,
         nav_observer.last_navigation_url().spec());
     nav_observer.StopWatchingNewWebContents();
   }
 
   MediaRouterAction* GetMediaRouterAction() {
     return MediaRouterDialogControllerImpl::GetOrCreateForWebContents(
@@ skipping 23 matching lines @@
   ToolbarActionsBar* toolbar_actions_bar_ = nullptr;
 
   Issue issue_;
 
   // A vector of MediaRoutes that includes a local route.
   std::vector<MediaRoute> routes_;
 
   MediaRouterActionController* action_controller_ = nullptr;
 };
 
-// TODO(crbug.com/658005): Fails on multiple platforms.
 IN_PROC_BROWSER_TEST_F(MediaRouterUIBrowserTest,
-                       DISABLED_OpenDialogWithMediaRouterAction) {
+                       OpenDialogWithMediaRouterAction) {
   // We start off at about:blank page.
   // Make sure there is 1 tab and media router is enabled.
   ASSERT_EQ(1, browser()->tab_strip_model()->count());
 
   SetAlwaysShowActionPref(true);
   EXPECT_TRUE(ActionExists());
 
   OpenMediaRouterDialogAndWaitForNewWebContents();
 
   // Reload the browser and wait.
@@ skipping 81 matching lines @@
   action_controller_->OnRoutesUpdated(std::vector<MediaRoute>(),
                                       std::vector<MediaRoute::Id>());
   EXPECT_FALSE(ActionExists());
   action_controller_->OnRoutesUpdated(routes_, std::vector<MediaRoute::Id>());
   EXPECT_TRUE(ActionExists());
   browser2->window()->Close();
   EXPECT_TRUE(ActionExists());
 }
 
 }  // namespace media_router