[gtk+] text view: Add diagram to CSS documentation

[Matthias Clasen <matthiasc src gnome org>]

commit a7076d1c4ca914e8fb4b148845a085cb7a818947
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Nov 3 13:49:07 2015 -0500

    text view: Add diagram to CSS documentation

 gtk/gtktextview.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index cab852a..3b8f16e 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -73,6 +73,15 @@
  *
  * # CSS nodes
  *
+ * |[<!-- language="plain" -->
+ * textview.view
+ * ├── border.top
+ * ├── border.left
+ * ├── text
+ * ├── border.right
+ * ╰── border.bottom
+ * ]|
+ *
  * GtkTextView has a main css node with name textview and style class .view,
  * and subnodes for each of the border windows, and the main text area,
  * with names border and text, respectively. The border nodes each get