core: add an NMExportedObject base class

Add NMExportedObject, make it the base class of all D-Bus-exported
types, and move the nm-properties-changed-signal logic into it. (Also,
make NMSettings use the same properties-changed code as everything
else, which it was not previously doing, presumably for historical
reasons).

(This is mostly just shuffling code around at this point, but
NMExportedObject will be more important in the gdbus port, since
gdbus-codegen doesn't do a very good job of supporting objects that
export multiple interfaces [as each NMDevice subclass does, for
example], so we will need more glue/helper code in NMExportedObject
then.)

src/nm-exported-object.h

@@ -0,0 +1,53 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
+/* NetworkManager -- Network link manager
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Copyright 2014 Red Hat, Inc.
+ */
+
+#ifndef NM_EXPORTED_OBJECT_H
+#define NM_EXPORTED_OBJECT_H
+
+#include <dbus/dbus-glib.h>
+
+#include "nm-glib.h"
+#include "nm-types.h"
+
+G_BEGIN_DECLS
+
+#define NM_TYPE_EXPORTED_OBJECT            (nm_exported_object_get_type ())
+#define NM_EXPORTED_OBJECT(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), NM_TYPE_EXPORTED_OBJECT, NMExportedObject))
+#define NM_EXPORTED_OBJECT_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass),  NM_TYPE_EXPORTED_OBJECT, NMExportedObjectClass))
+#define NM_IS_EXPORTED_OBJECT(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), NM_TYPE_EXPORTED_OBJECT))
+#define NM_IS_EXPORTED_OBJECT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass),  NM_TYPE_EXPORTED_OBJECT))
+#define NM_EXPORTED_OBJECT_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj),  NM_TYPE_EXPORTED_OBJECT, NMExportedObjectClass))
+
+typedef struct {
+	GObject parent;
+} NMExportedObject;
+
+typedef struct {
+	GObjectClass parent;
+} NMExportedObjectClass;
+
+GType nm_exported_object_get_type (void);
+
+void nm_exported_object_class_add_interface (NMExportedObjectClass *object_class,
+                                             const DBusGObjectInfo *info);
+
+G_END_DECLS
+
+#endif	/* NM_EXPORTED_OBJECT_H */