Refactor web shell integration tests utilities.

ios/web/shell/test/web_shell_test_util.mm

Index: ios/web/shell/test/web_shell_test_util.mm
diff --git a/ios/web/shell/test/web_shell_test_util.mm b/ios/web/shell/test/web_shell_test_util.mm
deleted file mode 100644
index 4cacb4f022e6d8042e40ac8f14682d326ff73b99..0000000000000000000000000000000000000000
--- a/ios/web/shell/test/web_shell_test_util.mm
+++ /dev/null
@@ -1,18 +0,0 @@
-// 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.
-
-#import "ios/web/shell/test/web_shell_test_util.h"
-
-#include <UIKit/UIKit.h>
-
-namespace web {
-namespace web_shell_test_util {
-
-ViewController* GetCurrentViewController() {
-  return (ViewController*)[[[[UIApplication sharedApplication] delegate] window]
-      rootViewController];
-}
-
-}  // namespace web_shell_test_util
-}  // namespace web