function getReferenceOffsets(state, popper, reference) {
  var commonOffsetParent = findCommonOffsetParent(popper, reference);
  return getOffsetRectRelativeToArbitraryNode(reference, commonOffsetParent);
}
Get offsets to the reference element
@method
@memberof Popper.Utils
@param {Object} state
@param {Element} popper - the popper element
@param {Element} reference - the reference element (the popper will be relative to this)
@returns {Object} An object containing the offsets which will be applied to the popper