Mac: Add "Show Tab Overview" menu item.

chrome/browser/app_controller_mac.h

Index: chrome/browser/app_controller_mac.h
diff --git a/chrome/browser/app_controller_mac.h b/chrome/browser/app_controller_mac.h
index e34e2b4c91b765cae86b65ab429dfb2985f71ede..ea08903528bea8b38c8e288e1927511cbb45b06b 100644
--- a/chrome/browser/app_controller_mac.h
+++ b/chrome/browser/app_controller_mac.h
@@ -50,6 +50,9 @@ class Profile;
   // Outlet for the help menu so we can bless it so Cocoa adds the search item
   // to it.
   IBOutlet NSMenu* helpMenu_;
+
+  // Outlet for the tabpose menu item so we can hide it.
+  IBOutlet NSMenuItem* tabposeMenuItem_;
 }
 
 @property(readonly, nonatomic) BOOL startupComplete;