Disable triple-click handling in IE

Because IE11's click counter is broken, the triple-click code
completely breaks editing in IE. For a real fix, we'd have to
reintroduce getClickCount() or whatever it's called, where we
keep track of the number of clicks ourselves.

Change-Id: Iaa8a5b8aed553f8dc296eca503d0aa5517a2c0e8