P2.1a.

chrome/browser/cocoa/hover_close_button.h

Index: chrome/browser/cocoa/hover_close_button.h
diff --git a/chrome/browser/cocoa/hover_close_button.h b/chrome/browser/cocoa/hover_close_button.h
index 7c343958c965f69e68dc267cdb992d991e8bc615..2d6f058ed74f6893a4568c8316e0fe8793e99b79 100644
--- a/chrome/browser/cocoa/hover_close_button.h
+++ b/chrome/browser/cocoa/hover_close_button.h
@@ -6,6 +6,8 @@
 
 #include "base/scoped_nsobject.h"
 
+@class TabController;
+
 // The standard close button for our Mac UI which is the "x"
 // that changes to the red circle with the "x" when you hover over it.
 // At this time it is used by the popup blocker, download bar, info bar
@@ -13,6 +15,8 @@
 @interface HoverCloseButton : NSButton {
   // Tracking area for close button mouseover images.
   scoped_nsobject<NSTrackingArea> closeTrackingArea_;
+
+  IBOutlet TabController* controller_;
 }
 
 // Enables or disables the |NSTrackingRect|s for the button.