Cannot set property 'isOpen' of null

[oliversalzburg]

I occasionally see the following error in the browser console in our application.

Uncaught TypeError: Cannot set property 'isOpen' of null
hide @ ui-bootstrap-tpls.js:3496
hideTooltipBind @ ui-bootstrap-tpls.js:3454

I can't definitively say what causes it, but I suspect that it happens when I have a tooltip on a link which, when clicked, causes a route change and, thus, destroys the current scope.

[RobJacobs]

This should be fixed under PR #4455 which fixed issue #3347. When reporting issues, please search closed issues and PRs first and provide a plunkr that reproduces the problem.