Make infobars ignore button clicks when closing.

chrome/browser/ui/gtk/infobars/infobar_gtk.h

Index: chrome/browser/ui/gtk/infobars/infobar_gtk.h
===================================================================
--- chrome/browser/ui/gtk/infobars/infobar_gtk.h	(revision 102206)
+++ chrome/browser/ui/gtk/infobars/infobar_gtk.h	(working copy)
@@ -60,12 +60,14 @@
   GtkWidget* CreateLabel(const std::string& text);
 
   // Creates a link button with the appropriate current gtk-theme state.
+  // NOTE: Subclasses must ignore link clicks if we're unowned.
   GtkWidget* CreateLinkButton(const std::string& text);
 
   // Adds |display_text| to the infobar. If |link_text| is not empty, it is
   // rendered as a hyperlink and inserted into |display_text| at |link_offset|,
   // or right aligned in the infobar if |link_offset| is |npos|. If a link is
   // supplied, |link_callback| must not be null. It will be invoked on click.
+  // NOTE: Subclasses must ignore link clicks if we're unowned.
   void AddLabelWithInlineLink(const string16& display_text,
                               const string16& link_text,
                               size_t link_offset,