[ios] Added deprecation comments and TODOs for ios/web classes/protocols

ios/web/public/web_state/crw_web_controller_observer.h

 // Copyright 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.
 
 #ifndef IOS_WEB_PUBLIC_WEB_STATE_CRW_WEB_CONTROLLER_OBSERVER_H_
 #define IOS_WEB_PUBLIC_WEB_STATE_CRW_WEB_CONTROLLER_OBSERVER_H_
 
 #import <Foundation/Foundation.h>
 
 @class CRWWebController;
 @protocol CRWWebViewProxy;
 
-// NOTE: When adding new methods to CRWWebControllerObserver, consider adding
-// them to WebStateObserver instead if they need to be surfaced to the public
-// API.
+// DEPRECATED, do not conform to this protocol and do not add any methods to it.
+// Use web::WebStateObserver instead.
+// TODO(crbug.com/675005): Remove this protocol.
 @protocol CRWWebControllerObserver<NSObject>
 
 @optional
 
 // Called when the current page is loaded.
 // DEPRECATED: Use WebStateObserver instead.
 - (void)pageLoaded:(CRWWebController*)webController;
 
 // Called when the web controller is about to close.
 - (void)webControllerWillClose:(CRWWebController*)webController;
 
 // Gives CRWWebControllerObservers access to the CRWWebViewProxy.
 - (void)setWebViewProxy:(id<CRWWebViewProxy>)webView
              controller:(CRWWebController*)webController;
 
 @end
 
 #endif  // IOS_WEB_PUBLIC_WEB_STATE_CRW_WEB_CONTROLLER_OBSERVER_H_