Destroy the GTK info bar container widget when the object is destroyed.

chrome/browser/gtk/infobar_container_gtk.cc

Index: chrome/browser/gtk/infobar_container_gtk.cc
diff --git a/chrome/browser/gtk/infobar_container_gtk.cc b/chrome/browser/gtk/infobar_container_gtk.cc
index 1b1094b66eeda6000f47af6791a5bcd327969f9c..cc8543d3a49873128a7170c8decfd83738087d13 100644
--- a/chrome/browser/gtk/infobar_container_gtk.cc
+++ b/chrome/browser/gtk/infobar_container_gtk.cc
@@ -46,6 +46,8 @@ InfoBarContainerGtk::InfoBarContainerGtk(BrowserWindow* browser_window)
 InfoBarContainerGtk::~InfoBarContainerGtk() {
   browser_window_ = NULL;
   ChangeTabContents(NULL);
+
+  container_.Destroy();
 }
 
 void InfoBarContainerGtk::ChangeTabContents(TabContents* contents) {