Force 'expand' child to have no transitions

If its size update were animated, the element could become smaller
than its parent, thus making impossible to scroll 'expand' to bottom
on further 'scroll' events and breaking the sensor.

Author: Alberto Villa

src/ResizeSensor.js

@@ -65,7 +65,7 @@
             element.resizeSensor = document.createElement('div');
             element.resizeSensor.className = 'resize-sensor';
             var style = 'position: absolute; left: 0; top: 0; right: 0; bottom: 0; overflow: hidden; z-index: -1; visibility: hidden;';
-            var styleChild = 'position: absolute; left: 0; top: 0;';
+            var styleChild = 'position: absolute; left: 0; top: 0; transition: 0s;';
 
             element.resizeSensor.style.cssText = style;
             element.resizeSensor.innerHTML =