src/HOL/ROOT

--- a/src/HOL/ROOT	Fri Apr 24 13:16:42 2020 +0000
+++ b/src/HOL/ROOT	Sat Apr 25 16:31:43 2020 +0200
@@ -240,6 +240,7 @@
     Tree_Map
     Interval_Tree
     AVL_Map
+    Height_Balanced_Tree
     RBT_Set2
     RBT_Map
     Tree23_Map