enthought/chaco — pull request #241 by corranwebster (2014-12-12 09:24:46+00:00)
Title: Add default position and tests for BetterZoom

Fixes #240.

The problem occurred when the tool was added with keyboard focus on the component and the mouse in the region where the tool was working. A keyboard interaction with the tool would then give a traceback because `position` was not defined.