Make chrome/ be documentElement/body agnostic with regards to scrollTop/Left

chrome/browser/resources/about_memory.js

Index: chrome/browser/resources/about_memory.js
diff --git a/chrome/browser/resources/about_memory.js b/chrome/browser/resources/about_memory.js
index e3a6871753b197f341c9781f12970c95bbc44671..56268579182f0a070fe991717a858edbca651680 100644
--- a/chrome/browser/resources/about_memory.js
+++ b/chrome/browser/resources/about_memory.js
@@ -2,8 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+<include src="../../../ui/webui/resources/js/util.js"></include>
+
 function reload() {
-  if (document.getElementById('helpTooltip'))
+  if ($('helpTooltip'))
     return;
   history.go(0);
 }
@@ -42,12 +44,14 @@ function handleHelpTooltipMouseOver(event) {
   var width = el.offsetWidth;
   var height = el.offsetHeight;
 
-  if (event.pageX - width - 50 + document.documentElement.scrollLeft >= 0)
+  var scrollLeft = scrollLeftForDocument(document);
+  if (event.pageX - width - 50 + scrollLeft >= 0)
     el.style.left = (event.pageX - width - 20) + 'px';
   else
     el.style.left = (event.pageX + 20) + 'px';
 
-  if (event.pageY - height - 50 + document.documentElement.scrollTop >= 0)
+  var scrollTop = scrollTopForDocument(document);
+  if (event.pageY - height - 50 + scrollTop >= 0)
     el.style.top = (event.pageY - height - 20) + 'px';
   else
     el.style.top = (event.pageY + 20) + 'px';
@@ -56,7 +60,7 @@ function handleHelpTooltipMouseOver(event) {
 }
 
 function handleHelpTooltipMouseOut(event) {
-  var el = document.getElementById('helpTooltip');
+  var el = $('helpTooltip');
   el.parentNode.removeChild(el);
 }
 
@@ -72,7 +76,7 @@ function enableHelpTooltips() {
 document.addEventListener('DOMContentLoaded', function() {
   // This is the javascript code that processes the template:
   var input = new JsEvalContext(loadTimeData.getValue('jstemplateData'));
-  var output = document.getElementById('t');
+  var output = $('t');
   jstProcess(input, output);
 
   enableHelpTooltips();