Fixed #654: removed unnecessary minimum height for groups, takes the height of the group label as minimum height now.

HISTORY.md

@@ -11,6 +11,8 @@ http://visjs.org
 ### Timeline
 
 - Orientation can now be configured separately for axis and items.
+- Fixed #654: removed unnecessary minimum height for groups, takes the
+  height of the group label as minimum height now.
 
 
 ## 2015-03-05, version 3.11.0

lib/timeline/component/Group.js

@@ -269,7 +269,7 @@ Group.prototype._calculateHeight = function (margin) {
     height = max + margin.item.vertical / 2;
   }
   else {
-    height = margin.axis + margin.item.vertical;
+    height = 0;
   }
   height = Math.max(height, this.props.label.height);