Unref the GC so it's destroy after we create it.

chrome/browser/autocomplete/autocomplete_popup_view_gtk.cc

Index: chrome/browser/autocomplete/autocomplete_popup_view_gtk.cc
diff --git a/chrome/browser/autocomplete/autocomplete_popup_view_gtk.cc b/chrome/browser/autocomplete/autocomplete_popup_view_gtk.cc
index cb62cb5ac7c3df74a27fdcaa6d11ac03dfceab2d..72a1c78c70790f000bec295bef9c8f9edd6b8a74 100644
--- a/chrome/browser/autocomplete/autocomplete_popup_view_gtk.cc
+++ b/chrome/browser/autocomplete/autocomplete_popup_view_gtk.cc
@@ -469,5 +469,7 @@ gboolean AutocompletePopupViewGtk::HandleExpose(GtkWidget* widget,
     }
   }
 
+  g_object_unref(gc);
+
   return TRUE;
 }