Remove lies about event objects being passed through

onFocusChange is debounced now, so it doesn't get a jQuery.Event
object passed to it any more. It was trying to pass this
nonexistent object to onDocumentFocus() and onDocumentBlur(),
which were already ignoring it anyway.

Change-Id: Ic29cea2b15626715eb6ddaf4f87b5279ffae36b3
Merge "Remove lies about event objects being passed through"