[Fixes #1243] Fix IE scrolling with mouse not working with overflow-y, fix focus loss in IE8

[septagram]

I may have been unable to fix this cleanly, unfortunately. The thing is the "blurred" event should not be fired by the Input object of the typeahead, but the preventDefault and stopImmediatePropagation in the event caught in _hacks did stop the event when overlow-y was used.

So I have moved the code for checking this into the Input class, because the _hacks are unfortunately not visible from there.

Also, I failed to figure out the build and testing system, sorry.

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