Error occurs when releasing a dragged click outside of browser window

[jansent]

In an Ionic Side Menu view the following error occurs when you click and drag to the side to bring out the menu and then release your click outside the boundaries of the browser window:

endEvent.target.classList is undefined
(endEvent.target.classList.contains('button') ? TAP_RELEASE_BUTTON_TOLERANCE
ionic.js (line 2917)

Should be a relatively easy fix. I'm sure this error would never happen on a mobile device but it is still worth patching.

See the issue on this codepen: http://codepen.io/ionic/pen/tcIGK

Click and drag to the right and release the click outside of the browser window. I should also mention that I am using beta 7, and this bug was present in 6 as well.

[jansent]

Awesome!

[ionitron-bot]

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