gtk: Document constants

gtk/gtkimcontextsimple.h

@@ -30,6 +30,13 @@ G_BEGIN_DECLS
  * No longer used by GTK, just left here on the off chance that some
  * 3rd party code used this define.
  */
+/**
+ * GTK_MAX_COMPOSE_LEN:
+ *
+ * Evaluates to the maximum length of a compose sequence.
+ *
+ * This macro is longer used by GTK.
+ */
 #define GTK_MAX_COMPOSE_LEN 7
 
 #define GTK_TYPE_IM_CONTEXT_SIMPLE              (gtk_im_context_simple_get_type ())

gtk/gtkimmodule.h

@@ -21,6 +21,11 @@
 
 G_BEGIN_DECLS
 
+/**
+ * GTK_IM_MODULE_EXTENSION_POINT_NAME:
+ *
+ * The default name of the extension point.
+ */
 #define GTK_IM_MODULE_EXTENSION_POINT_NAME "gtk-im-module"
 
 G_END_DECLS

gtk/gtkmediafile.h

@@ -27,6 +27,11 @@
 
 G_BEGIN_DECLS
 
+/**
+ * GTK_MEDIA_FILE_EXTENSION_POINT_NAME:
+ *
+ * The default extension point name for media file.
+ */
 #define GTK_MEDIA_FILE_EXTENSION_POINT_NAME "gtk-media-file"
 
 #define GTK_TYPE_MEDIA_FILE             (gtk_media_file_get_type ())