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

ios/shared/chrome/browser/tabs/web_state_list.h

Index: ios/shared/chrome/browser/tabs/web_state_list.h
diff --git a/ios/shared/chrome/browser/tabs/web_state_list.h b/ios/shared/chrome/browser/tabs/web_state_list.h
deleted file mode 100644
index 5aff6ef90fbf352561d4d09bdac8f48f54bd7f3e..0000000000000000000000000000000000000000
--- a/ios/shared/chrome/browser/tabs/web_state_list.h
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright 2017 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_SHARED_CHROME_BROWSER_TABS_WEB_STATE_LIST_H_
-#define IOS_SHARED_CHROME_BROWSER_TABS_WEB_STATE_LIST_H_
-
-#import <Foundation/Foundation.h>
-
-@protocol WebStateHandle;
-
-// Clang format incorrectly formats the <__covariant ObjectType> used
-// to declare WebStateList as a lighweight generic class. Disable it
-// until the underlying issue is fixed (b/34375672).
-// clang-format off
-
-// A generic array of WebStateHandles.
-@interface WebStateList<__covariant ObjectType: id<WebStateHandle>>
-    : NSObject<NSFastEnumeration>
-
-// The number of objects in the array.
-@property(nonatomic, readonly) NSUInteger count;
-
-// The first WebStateHandle in the array.
-@property(nonatomic, readonly) ObjectType firstWebState;
-
-// Inserts |webState| at the end of the array.
-- (void)addWebState:(ObjectType)webState;
-
-// Inserts |webState| into the array at |index|.
-- (void)insertWebState:(ObjectType)webState atIndex:(NSUInteger)index;
-
-// Replaces the WebStateHandle at |index| with |webState|.
-- (void)replaceWebStateAtIndex:(NSUInteger)index
-                  withWebState:(ObjectType)webState;
-
-// Removes all occurrences of |webState| in the array.
-- (void)removeWebState:(ObjectType)webState;
-
-// Returns YES if |webState| is in the array.
-- (BOOL)containsWebState:(ObjectType)webState;
-
-// Returns the WebStateHandle at |index|.
-- (ObjectType)webStateAtIndex:(NSUInteger)index;
-
-// Returns the lowest index whose value is equal to |webState|.
-- (NSUInteger)indexOfWebState:(ObjectType)webState;
-
-@end
-
-// clang-format on
-
-#endif  // IOS_SHARED_CHROME_BROWSER_TABS_WEB_STATE_LIST_H_