Fixes a DCHECK in tools_menu_button_observer_bridge during tests

ios/chrome/browser/ui/omnibox_perftest.mm

 // 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.
 
 #import <UIKit/UIKit.h>
 
 #include <memory>
 
 #include "base/memory/ptr_util.h"
 #import "base/test/ios/wait_util.h"
@@ skipping 197 matching lines @@
   std::unique_ptr<WebStateList> web_state_list_;
   std::unique_ptr<ToolbarModelDelegateIOS> toolbar_model_delegate_;
   std::unique_ptr<ToolbarModelIOS> toolbar_model_ios_;
   WebToolbarController* toolbar_;
   UIWindow* window_;
   KeyboardAppearanceListener* keyboard_listener_;
 };
 
 // Measures the amount of time it takes the Omnibox text field to activate
 // the on-screen keyboard.
-// TODO(crbug.com/717300): Test disabled because of a DCHECK in Reading List.
-TEST_F(OmniboxPerfTest, DISABLED_TestTextFieldDidBeginEditing) {
+TEST_F(OmniboxPerfTest, TestTextFieldDidBeginEditing) {
   LogPerfTiming("Keyboard preload", PreLoadKeyboard());
   OmniboxTextFieldIOS* textField = (OmniboxTextFieldIOS*)FindViewByClass(
       [toolbar_ view], [OmniboxTextFieldIOS class]);
 
   // Time how long it takes to "focus" on omnibox.
   RepeatTimedRuns("Begin editing",
                   ^base::TimeDelta(int index) {
                     return EnableKeyboard(textField);
                   },
                   ^() {
@@ skipping 42 matching lines @@
         }
         NSLog(@"%2d: %@", index, logMessage);
         return elapsed;
       },
       ^() {
         [textField setText:@""];
         DisableKeyboard(textField);
       });
 }
 }