Add wxWindowGTK::GTKConnectWidget() helper.

This trivial wrapper function allows to omit "m_widget" and "this" arguments
when calling g_signal_connect().

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@62275 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/window.cpp

@@ -2382,6 +2382,11 @@ void wxWindowGTK::PostCreation()
         gtk_widget_show( m_widget );
 }
 
+gulong wxWindowGTK::GTKConnectWidget(const char *signal, void (*callback)())
+{
+    return g_signal_connect(m_widget, signal, callback, this);
+}
+
 void wxWindowGTK::ConnectWidget( GtkWidget *widget )
 {
     g_signal_connect (widget, "key_press_event",