Refactor web shell integration tests utilities.

ios/web/shell/test/navigation_test_util.mm

-// Copyright 2016 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 "ios/web/shell/test/navigation_test_util.h"
-
-#import "ios/web/public/navigation_manager.h"
-#import "ios/web/public/web_state/web_state.h"
-#import "ios/web/shell/test/web_shell_test_util.h"
-
-using web::NavigationManager;
-
-namespace web {
-namespace navigation_test_util {
-// TODO(crbug.com/604902): Refactor these utilities into objects that can be
-// shared accross the web shell and Chrome.
-
-void LoadUrl(GURL url) {
-  ViewController* view_controller =
-      web::web_shell_test_util::GetCurrentViewController();
-
-  NavigationManager* navigation_manager =
-      [view_controller webState]->GetNavigationManager();
-  NavigationManager::WebLoadParams params(url);
-  params.transition_type = ui::PAGE_TRANSITION_TYPED;
-  navigation_manager->LoadURLWithParams(params);
-}
-
-}  // namespace navigation_test_util
-}  // namespace web