This file tests the code to determine mouse position and element position with respect to the document or viewport.
dojo.style.getAbsolutePosition(xyz, true) tells you where you would position a node inside document.body such that it was on top of xyz. It works well in conjunction with event.pageX/Y.
dojo.style.getAbsolutePosition(xyz, false) returns the position that would be returned by event.clientX/Y if the mouse were directly over the top/left of this node.
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