The event "mousedown" is not fired on mobile properly

I'm using 'react-dates' library and on my iphone5 handler `onOutsideClick` is not fired properly.
It's fired when I click on the button, but not if I click on an empty space background.

I've added 'touchstart' event for my component and now it's fine.

Can we extend current event listener with `touchstart`?

Review the component's existing mousedown event listener and the reported onOutsideClick behavior, starting with the event-handling entry point. Verify the iPhone/touch case described in the issue; done means touches on empty mobile background trigger onOutsideClick as requested.

Written by the indexing model from the issue text.