angular-ui/bootstrap — pull request #2151 by mattslocum (2014-05-06 05:01:44+00:00)
Title: Tooltip :: Enable ngModel to use parent scope

Tooltip used to use a child scope. So elements that use ng-model with primitives don't update the parent scope. http://jsfiddle.net/mslocum/CEqA8/

Solution:
This makes ngModel still have 2-way data binding with elements. http://jsfiddle.net/mslocum/CEqA8/1