Bug 1187649 - Free constructed widget path in nsLookAndFeel on GTK. r=karlt

widget/gtk/mozgtk/mozgtk.c

@@ -546,6 +546,7 @@ STUB(gtk_tree_view_column_get_button)
 STUB(gtk_widget_get_preferred_size)
 STUB(gtk_widget_get_style_context)
 STUB(gtk_widget_path_append_type)
+STUB(gtk_widget_path_free)
 STUB(gtk_widget_path_new)
 STUB(gtk_widget_set_visual)
 STUB(gtk_app_chooser_dialog_new_for_content_type)

widget/gtk/nsLookAndFeel.cpp

@@ -1223,6 +1223,7 @@ nsLookAndFeel::Init()
                          nullptr);
 
     gtk_widget_destroy(window);
+    gtk_widget_path_free(path);
 }
 
 // virtual