[ObjC ARC] Converts ios/chrome/browser/ui/tabs:tabs to ARC.

ios/chrome/browser/ui/tabs/tab_view.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_UI_TABS_TAB_VIEW_H_
 #define IOS_CHROME_BROWSER_UI_TABS_TAB_VIEW_H_
 
 #import <UIKit/UIKit.h>
 
 #include "base/mac/scoped_nsobject.h"
 #import "ios/chrome/browser/tabs/tab.h"
 
 @class GTMFadeTruncatingLabel;
 
 // View class that draws a Chrome-style tab.
 @interface TabView : UIControl
 
-@property(nonatomic, readonly, retain) UIButton* closeButton;
-@property(nonatomic, readonly, retain) GTMFadeTruncatingLabel* titleLabel;
-@property(nonatomic, retain) UIImage* favicon;
+@property(nonatomic, readonly, strong) UIButton* closeButton;
+@property(nonatomic, readonly, strong) GTMFadeTruncatingLabel* titleLabel;
+@property(nonatomic, strong) UIImage* favicon;
 @property(nonatomic, assign, getter=isCollapsed) BOOL collapsed;
-@property(nonatomic, retain) UIImage* background;
+@property(nonatomic, strong) UIImage* background;
 @property(nonatomic, assign) BOOL incognitoStyle;
 
 // Designated initializer.  Creates a TabView with frame equal to CGRectZero.
 // If |emptyView| is YES, it creates a TabView without buttons or spinner.
 // |selected|, the selected state of the tab, is provided to ensure the
 // background is drawn correctly the first time, rather than requiring that
 // -setSelected be called in order for it to be drawn correctly.
 - (id)initWithEmptyView:(BOOL)emptyView selected:(BOOL)selected;
 
 // Sets the title.
 - (void)setTitle:(NSString*)title;
 // Starts the progress spinner animation.
 - (void)startProgressSpinner;
 // Stops the progress spinner animation.
 - (void)stopProgressSpinner;
 
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_TABS_TAB_VIEW_H_