[ios] WebStateList owns all WebState it manages.

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/mac/scoped_nsobject.h"
 #include "base/memory/ptr_util.h"
@@ skipping 57 matching lines @@
     // Sets up the listener for keyboard activation/deactivation notifications.
     keyboard_listener_.reset([[KeyboardAppearanceListener alloc] init]);
 
     // Create a real window to host the Toolbar.
     CGRect screenBounds = [[UIScreen mainScreen] bounds];
     window_.reset([[UIWindow alloc] initWithFrame:screenBounds]);
     [window_ makeKeyAndVisible];
 
     // Create a WebStateList that will always return the test WebState as
     // the active WebState.
-    web_state_list_ = base::MakeUnique<WebStateList>(
-        &web_state_list_delegate_, WebStateList::WebStateOwned);
+    web_state_list_ = base::MakeUnique<WebStateList>(&web_state_list_delegate_);
     std::unique_ptr<web::TestWebState> web_state =
         base::MakeUnique<web::TestWebState>();
-    web_state_list_->InsertWebState(0, web_state.release());
+    web_state_list_->InsertWebState(0, std::move(web_state));
 
     // Creates the Toolbar for testing and sizes it to the width of the screen.
     toolbar_model_delegate_.reset(
         new ToolbarModelDelegateIOS(web_state_list_.get()));
     toolbar_model_ios_.reset(
         new ToolbarModelImplIOS(toolbar_model_delegate_.get()));
 
     // The OCMOCK_VALUE macro doesn't like std::unique_ptr, but it works just
     // fine if a temporary variable is used.
     ToolbarModelIOS* model_for_mock = toolbar_model_ios_.get();
@@ skipping 105 matching lines @@
         },
         ^bool() {
           return ![keyboard_listener_ isKeyboardVisible];
         },
         false, base::TimeDelta());
   }
 
   std::unique_ptr<TestChromeBrowserState> chrome_browser_state_;
   FakeWebStateListDelegate web_state_list_delegate_;
   std::unique_ptr<WebStateList> web_state_list_;
-  web::WebState* web_state_;
   std::unique_ptr<ToolbarModelDelegateIOS> toolbar_model_delegate_;
   std::unique_ptr<ToolbarModelIOS> toolbar_model_ios_;
   base::scoped_nsobject<WebToolbarController> toolbar_;
   base::scoped_nsobject<UIWindow> window_;
   base::scoped_nsobject<KeyboardAppearanceListener> keyboard_listener_;
 };
 
 // Measures the amount of time it takes the Omnibox text field to activate
 // the on-screen keyboard.
 TEST_F(OmniboxPerfTest, TestTextFieldDidBeginEditing) {
@@ skipping 50 matching lines @@
         }
         NSLog(@"%2d: %@", index, logMessage);
         return elapsed;
       },
       ^() {
         [textField setText:@""];
         DisableKeyboard(textField);
       });
 }
 }