Revert of WebStateList is an array of web::WebState* wrappers.

ios/chrome/browser/tabs/tab_model.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_CHROME_BROWSER_TABS_TAB_MODEL_H_
 #define IOS_CHROME_BROWSER_TABS_TAB_MODEL_H_
 
 #import <Foundation/Foundation.h>
 #import <UIKit/UIKit.h>
 
 #include <memory>
 
-#import "ios/chrome/browser/tabs/tab.h"
-#import "ios/shared/chrome/browser/tabs/web_state_list.h"
 #import "ios/web/public/navigation_manager.h"
 #include "ui/base/page_transition_types.h"
 
 class GURL;
 class SessionID;
 @class SessionServiceIOS;
 @class SessionWindowIOS;
+@class Tab;
 @protocol TabModelObserver;
 class TabModelSyncedWindowDelegate;
 class TabUsageRecorder;
 
 namespace ios {
 class ChromeBrowserState;
 }
 
 namespace web {
 struct Referrer;
@@ skipping 43 matching lines @@
 // on the position where the tab will be open.
 NSUInteger const kTabPositionAutomatically = NSNotFound;
 
 }  // namespace TabModelConstants
 
 // A model of a tab "strip". Although the UI representation may not be a
 // traditional strip at all, tabs are still accessed via an integral index.
 // The model knows about the currently selected tab in order to maintain
 // consistency between multiple views that need the current tab to be
 // synchronized.
-@interface TabModel : WebStateList<Tab*>
+@interface TabModel : NSObject<NSFastEnumeration>
 
 // Currently active tab.
 @property(nonatomic, weak) Tab* currentTab;
 
 // The delegate for sync.
 @property(nonatomic, readonly)
     TabModelSyncedWindowDelegate* syncedWindowDelegate;
 
 // BrowserState associated with this TabModel.
 @property(nonatomic, readonly) ios::ChromeBrowserState* browserState;
@@ skipping 10 matching lines @@
 // Defaults to NO.
 // Note that generally this should be set via BVC, not directly.
 @property(nonatomic, assign) BOOL webUsageEnabled;
 
 // YES if this tab set is off the record.
 @property(nonatomic, readonly, getter=isOffTheRecord) BOOL offTheRecord;
 
 // NO if the model has at least one tab.
 @property(nonatomic, readonly, getter=isEmpty) BOOL empty;
 
+// Determines the number of tabs in the model.
+@property(nonatomic, readonly) NSUInteger count;
+
 // Initializes tabs from a restored session. |-setCurrentTab| needs to be called
 // in order to display the views associated with the tabs. Waits until the views
 // are ready. |browserState| cannot be nil. |service| cannot be nil; this class
 // creates intermediate SessionWindowIOS objects which must be consumed by a
 // session service before they are deallocated. |window| can be nil to create
 // an empty TabModel. In that case no notification will be sent during object
 // creation.
 - (instancetype)initWithSessionWindow:(SessionWindowIOS*)window
                        sessionService:(SessionServiceIOS*)service
                          browserState:(ios::ChromeBrowserState*)browserState
@@ skipping 181 matching lines @@
 // TYPED.
 - (Tab*)insertTabWithURL:(const GURL&)URL
                 referrer:(const web::Referrer&)referrer
               windowName:(NSString*)windowName
                   opener:(Tab*)parentTab
                  atIndex:(NSUInteger)index;
 
 @end
 
 #endif  // IOS_CHROME_BROWSER_TABS_TAB_MODEL_H_