Documentation change for new wxRTC function

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64749 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/richtext/richtextctrl.h

@@ -1179,6 +1179,13 @@ public:
     */
     virtual void PaintBackground(wxDC& dc);
 
+    /**
+        Other user defined painting after everything else (i.e. all text) is painted.
+
+        @since 2.9.1
+    */
+    virtual void PaintAboveContent(wxDC& dc);
+
     /**
         Pastes content from the clipboard to the buffer.
     */