Fix link highlights on links that contain images.

LayoutTests/compositing/gestures/resources/link-highlight-helper.js

+function createSquareCompositedHighlight(node)
+{
+  return _createHighlight(node, "squaredHighlight highlightDiv composited");
+}
+
 function createCompositedHighlight(node)
 {
   return _createHighlight(node, "highlightDiv composited");
 }
 
 function createHighlight(node)
 {
   return _createHighlight(node, "highlightDiv");
 }
 
@@ skipping 21 matching lines @@
       if ( !isNaN( elem.offsetLeft ) )
           offsetLeft += elem.offsetLeft - elem.scrollLeft;
 
       if ( !isNaN( elem.offsetTop ) )
           offsetTop += elem.offsetTop - elem.scrollTop;
 
     } while( elem = elem.offsetParent );
     return { top : offsetTop,
              left : offsetLeft };
 }