ios: Cleanup class/struct forward declarations

ios/public/provider/chrome/browser/ui/infobar_view_protocol.h

 // Copyright 2013 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_PUBLIC_PROVIDER_CHROME_BROWSER_UI_INFOBAR_VIEW_PROTOCOL_H_
 #define IOS_PUBLIC_PROVIDER_CHROME_BROWSER_UI_INFOBAR_VIEW_PROTOCOL_H_
 
 #import <CoreGraphics/CoreGraphics.h>
 #import <Foundation/Foundation.h>
 
-class InfoBarViewDelegate;
 @class UIImage;
 
 // Interface for setting up the infobar's widgets.
 @protocol InfoBarViewProtocol
 // How much of infobar is visible. The infobar is only partly visible during
 // showing/hiding animation.
 @property(nonatomic, assign) CGFloat visibleHeight;
 // Label text with links initialized with |stringAsLink:|.
 @property(nonatomic, readonly) NSString* markedLabel;
 
@@ skipping 46 matching lines @@
 // Adds to the infobar a switch and an adjacent label.
 - (void)addSwitchWithLabel:(NSString*)label
                       isOn:(BOOL)isOn
                        tag:(NSInteger)tag
                     target:(id)target
                     action:(SEL)action;
 
 @end
 
 #endif  // IOS_PUBLIC_PROVIDER_CHROME_BROWSER_UI_INFOBAR_VIEW_PROTOCOL_H_