Show Media Router toolbar icon ephemerally for MR dialogs

chrome/browser/ui/toolbar/media_router_action_unittest.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/macros.h"
 #include "chrome/browser/extensions/browser_action_test_util.h"
 #include "chrome/browser/extensions/extension_action_test_util.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/browser/ui/toolbar/media_router_action.h"
@@ skipping 61 matching lines @@
     return platform_delegate_;
   }
 
   MediaRouterDialogControllerImpl* controller_;
   MediaRouterActionPlatformDelegate* platform_delegate_;
 };
 
 class MediaRouterActionUnitTest : public MediaRouterTest {
  public:
   MediaRouterActionUnitTest()
-      : toolbar_model_(nullptr),
+      : MediaRouterTest(true),
+        toolbar_model_(nullptr),
         fake_issue_notification_(media_router::Issue(
             "title notification",
             "message notification",
             media_router::IssueAction(media_router::IssueAction::TYPE_DISMISS),
             std::vector<media_router::IssueAction>(),
             "route_id",
             media_router::Issue::NOTIFICATION,
             false,
             -1)),
         fake_issue_warning_(
@@ skipping 269 matching lines @@
   EXPECT_CALL(*mock_delegate, OnPopupClosed()).Times(1);
   action()->ExecuteAction(true);
   EXPECT_FALSE(dialog_controller->IsShowingMediaRouterDialog());
 
   EXPECT_CALL(*mock_delegate, OnPopupShown(true)).Times(1);
   dialog_controller->CreateMediaRouterDialog();
 
   EXPECT_CALL(*mock_delegate, OnPopupClosed()).Times(1);
   dialog_controller->HideMediaRouterDialog();
 }