[gtk/matthiasc/for-master] icontheme: Clarify the docs

[Matthias Clasen <matthiasc src gnome org>]

commit 00b101cc377df153d42b45ca2a5c0f5ae76d2af9
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Sep 30 08:01:50 2020 -0400

    icontheme: Clarify the docs
    
    Mention that icons directly in /$app_id/icons/ are treated
    as unthemed icons.
    
    See #3216

 gtk/gtkicontheme.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkicontheme.c b/gtk/gtkicontheme.c
index 848d2848fa..49d16d5ca5 100644
--- a/gtk/gtkicontheme.c
+++ b/gtk/gtkicontheme.c
@@ -1542,9 +1542,12 @@ gtk_icon_theme_add_search_path (GtkIconTheme *self,
  *
  * The resources are considered as part of the hicolor icon theme
  * and must be located in subdirectories that are defined in the
- * hicolor icon theme, such as `@path/16x16/actions/run.png`.
+ * hicolor icon theme, such as `@path/16x16/actions/run.png`
+ * or `@path/scalable/actions/run.svg`.
+ *
  * Icons that are directly placed in the resource path instead
- * of a subdirectory are also considered as ultimate fallback.
+ * of a subdirectory are also considered as ultimate fallback,
+ * but they are treated like unthemed icons.
  */
 void
 gtk_icon_theme_set_resource_path (GtkIconTheme       *self,