Error Notice on drupal 7: Undefined index: module in _field_info_prepare_instance_widget()

While working on a fresh install of the latest Commons-7.x-3.x-dev version and adding in additional modules, I'd get the same error with any/every scenario - from forgetting a dependency, to rollbacks and/or uninstalls. I came across a similar error report with filefield_paths (http://drupal.org/node/1601104), and it prompted a look at the field.info.inc line#386 to see if the same type of fix could apply.

A change from:
$widget['module'] = $widget_type['module'];
to:
$widget['module'] = isset($widget_type['module']) ? $widget_type['module'] : NULL;
seems to have quieted the notice messages.

Commons dev shows the Drupal base at 7.15, and this may have been discovered/fixed in the standard D7 core... so this is more informational for someone in a similar situation