Classification Tree Example broken in 3.3.9

[michelemostarda]

Orange version

Orange 3.3.9

Expected behavior

The Classification Tree Example loads correctly.

Actual behavior

The Classification Tree Example misses a widget and relative connections.

It shows the popup Error occurred while loading the workflow.
UnknownWidgetDefinition('Orange.widgets.classify.owclassificationtreegraph.OWClassificationTreeGraph',)

Steps to reproduce the behavior

Help > Examples > choose Classification Tree

Additional info (worksheets, data, screenshots, ...)

It shows the popup Error occurred while loading the workflow.
UnknownWidgetDefinition('Orange.widgets.classify.owclassificationtreegraph.OWClassificationTreeGraph',)

[ajdapretnar]

Fixed in #1804.

[ajdapretnar]

Thank you for reporting the issue, we appreciate it. 😃