CHROMEG_VIRTUAL_CALLBACK_0 41 chrome/browser/ui/libgtk2ui/gtk2_signal.h CHROMEG_VIRTUAL_CALLBACK_0(CLASS, RETURN, METHOD, GtkWidget*); CHROMEG_VIRTUAL_CALLBACK_0 41 ui/base/gtk/gtk_signal.h CHROMEG_VIRTUAL_CALLBACK_0(CLASS, RETURN, METHOD, GtkWidget*);