Gtk2::MenuItem: document that new() is new_with_mnemonic() when an arg is given
Gtk2::MenuItem: document that new() is new_with_mnemonic() when an arg is given

https://bugzilla.gnome.org/show_bug.cgi?id=633410

cpanxaoc/perl-Gtk2,cpanxaoc/perl-Gtk2,cpanxaoc/perl-Gtk2