[gtk+] popover: Document differentiating style classes

[Matthias Clasen <matthiasc src gnome org>]

commit e56bb49407534297fa74c194783301d8fc1bb844
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Nov 2 12:53:57 2015 -0500

    popover: Document differentiating style classes
    
    There's a lot of popover variations out there.

 gtk/gtkpopover.c |   13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)
---
diff --git a/gtk/gtkpopover.c b/gtk/gtkpopover.c
index 1861dfb..b9e30fb 100644
--- a/gtk/gtkpopover.c
+++ b/gtk/gtkpopover.c
@@ -71,9 +71,16 @@
  * </section>
  * ]|
  *
- * A popover has a single css node called "popover" and gets the
- * .menu style class in case it has been created using
- * gtk_popover_new_from_model.
+ * # CSS nodes
+ *
+ * GtkPopover has a single css node called popover and gets the
+ * .menu style class if it is menu-like (e.g. #GtkPopoverMenu or
+ * created using gtk_popover_new_from_model().
+ *
+ * Particular uses of GtkPopover, such as touch selection popups
+ * or magnifiers in #GtkEntry or #GtkTextView get style classes
+ * like .touch-selection or .magnifier to differentiate from
+ * plain popovers.
  *
  * Since: 3.12
  */