fix for 27454 - Fade out close button state on mouse exit

chrome/browser/ui/cocoa/hover_button.h

Index: chrome/browser/ui/cocoa/hover_button.h
diff --git a/chrome/browser/ui/cocoa/hover_button.h b/chrome/browser/ui/cocoa/hover_button.h
index 022c12073bd98a69c1917a5d2e1e923877302f69..e2f8f999f266928aced07d1478759afa9b000350 100644
--- a/chrome/browser/ui/cocoa/hover_button.h
+++ b/chrome/browser/ui/cocoa/hover_button.h
@@ -5,6 +5,8 @@
 #import <Cocoa/Cocoa.h>
 
 #include "base/memory/scoped_nsobject.h"
+#include "chrome/browser/ui/cocoa/tracking_area.h"
+
 
 // A button that changes when you hover over it and click it.
 @interface HoverButton : NSButton {
@@ -21,10 +23,12 @@
 
  @private
   // Tracking area for button mouseover states.
-  scoped_nsobject<NSTrackingArea> trackingArea_;
+  ScopedCrTrackingArea trackingArea_;
 }
 
-// Enables or disables the |NSTrackingRect|s for the button.
+@property(nonatomic) HoverState hoverState;
+
+// Enables or disables the tracking for the button.
 - (void)setTrackingEnabled:(BOOL)enabled;
 
 // Checks to see whether the mouse is in the button's bounds and update