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

ios/chrome/browser/ui/tabs/tab_view.h

Index: ios/chrome/browser/ui/tabs/tab_view.h
diff --git a/ios/chrome/browser/ui/tabs/tab_view.h b/ios/chrome/browser/ui/tabs/tab_view.h
index 4e2d811d575db683f362d79b5f444404c1d2a431..d880b415cf10c84c0a065ebfe021b536a566888c 100644
--- a/ios/chrome/browser/ui/tabs/tab_view.h
+++ b/ios/chrome/browser/ui/tabs/tab_view.h
@@ -15,11 +15,11 @@
 // 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.