Created attachment 182394 [details] [review]
D-Bus: Support BusName sender parameter in signals

Now a client can define a signal with a GLib.BusName parameter, and
that will be used for showing the sender name.

If a server defines a signal with a GLib.BusName parameter, it will be
ignored when sending the dbus signal.

Like:

[DBus (name = "org.example.Demo")]
interface Demo : Object {
    public abstract int ping (string msg) throws IOError;
    public signal void pong (int count, string msg, GLib.BusName sender);
}
...
demo.pong.connect((c, m, s) => {
    stdout.printf ("Got pong %d for msg '%s' from sender '%s'\n", c, m, s);
    loop.quit ();
});

Actually the generated code is compiled with a warning, due the usage of the sender const char* string; I guess that strdup'ing it, the warning will go away; but is it so important?

The patch couldn't apply directly since it depends on the one attached on bug 643744