Merge pull request google#978 from rachel-fenichel/feature/developer_…

…background

Set background color to lilac if opening the playground from file:

tests/playground.html

@@ -64,6 +64,8 @@
 var fakeDragStack = [];
 
 function start() {
+  setBackgroundColor();
+
   // Parse the URL arguments.
   var match = location.search.match(/dir=([^&]+)/);
   var rtl = match && match[1] == 'rtl';
@@ -117,6 +119,17 @@
   taChange();
 }
 
+function setBackgroundColor() {
+  var lilac = '#d6d6ff';
+
+  var currentPage = window.location.href;
+  var regexFile = /^file[\S]*$/;
+
+  if (regexFile.test(currentPage)) {
+    document.getElementsByTagName('body')[0].style.backgroundColor = lilac;
+  }
+}
+
 function getToolboxElement() {
   var match = location.search.match(/toolbox=([^&]+)/);
   return document.getElementById('toolbox-' + (match ? match[1] : 'categories'));