rem: return elem.ownerDocument .defaultView .getComputedStyle(aElem, "").getPropertyValue(prop); 
add: return aElem.ownerDocument .defaultView .getComputedStyle(aElem, "").getPropertyValue(aProp); 
context:   getComputedStyle: function(aElem, aProp) {    return elem.ownerDocument               .defaultView               .getComputedStyle(aElem, "").getPropertyValue(prop);  },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/9421/539d0b696b6a1533be37f40f77a70624a1f537d3/nsContextMenu.js/clean/browser/base/content/nsContextMenu.js