Marcel Taeumel uploaded a new version of ToolBuilder-MVC to project The Trunk:
http://source.squeak.org/trunk/ToolBuilder-MVC-mt.40.mcz

==================== Summary ====================

Name: ToolBuilder-MVC-mt.40
Author: mt
Time: 12 April 2015, 7:12:26.033 pm
UUID: a81e1177-3c7e-794a-a1d3-a7f6e2031070
Ancestors: ToolBuilder-MVC-mt.39

Do not try to give nil as tree spec. We have fall-backs for this.

=============== Diff against ToolBuilder-MVC-mt.39 ===============

Item was removed:
- ----- Method: MVCToolBuilder>>pluggableTreeSpec (in category 'defaults') -----
- pluggableTreeSpec
- 	"We have no tree widget in MVC right now"
- 	^nil!