introspection: minor annotation additions

https://bugzilla.gnome.org/show_bug.cgi?id=731541

gst/gstdevice.c

@@ -264,8 +264,8 @@ gst_device_reconfigure_element (GstDevice * device, GstElement * element)
 /**
  * gst_device_has_classesv:
  * @device: a #GstDevice
- * @classes: a %NULL terminated array of klasses to match, only match if all
- *  classes are matched
+ * @classes: (array zero-terminated=1): a %NULL terminated array of klasses to match, only match if all
+ *   classes are matched
  *
  * Check if @factory matches all of the given classes
  *

gst/gstdevicemonitorfactory.c

@@ -459,8 +459,8 @@ gst_device_monitor_factory_get_metadata_keys (GstDeviceMonitorFactory * factory)
 /**
  * gst_device_monitor_factory_has_classesv:
  * @factory: a #GstDeviceMonitorFactory
- * @classes: a %NULL terminated array of klasses to match, only match if all
- *  classes are matched
+ * @classes: (array zero-terminated=1): a %NULL terminated array of
+ *   klasses to match, only match if all classes are matched
  *
  * Check if @factory matches all of the given classes
  *

gst/gstevent.c

@@ -348,10 +348,11 @@ gst_event_get_structure (GstEvent * event)
  *
  * Get a writable version of the structure.
  *
- * Returns: The structure of the event. The structure is still
- * owned by the event, which means that you should not free it and
- * that the pointer becomes invalid when you free the event.
- * This function checks if @event is writable and will never return %NULL.
+ * Returns: (transfer none): The structure of the event. The structure
+ * is still owned by the event, which means that you should not free
+ * it and that the pointer becomes invalid when you free the event.
+ * This function checks if @event is writable and will never return
+ * %NULL.
  *
  * MT safe.
  */