Update CSS tests to revision 31d63cc79bd4c929ed582229e936d7b389f3e6ab

tests/wpt/css-tests/css21_dev/xhtml1print/reference/background-root-013-ref.xht

@@ -0,0 +1,54 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml">
+
+ <head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+
+  <title>CSS Reftest Reference</title>
+  <style type="text/css">
+    @page { font: italic 8pt sans-serif; color: gray;
+            margin: 7%;
+            counter-increment: page;
+            @top-left { content: "CSS 2.1 Conformance Test Suite"; }
+            @top-right { content: "Test background-root-013-ref"; }
+            @bottom-right { content: counter(page); }
+          }
+</style>
+
+  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/" />
+
+  <style type="text/css"><![CDATA[
+  body
+  {
+  background-color: navy;  
+  border: blue solid; 
+  color: white; 
+  margin: 1em 5%; 
+  padding: 1em;
+  }
+
+  div
+  {
+  background: green url("support/square-purple.png") no-repeat center;
+  border: lime solid;
+  margin: 1em 30% 1em 5%;
+  padding: 1em;
+  }
+
+  div > div
+  {
+  border: none;
+  margin: 1em 5%;
+  padding: 1em;
+  }
+  ]]></style>
+
+ </head>
+
+ <body>
+
+  <div>
+    <div>In the middle of this green box with the bright green border, there should be a purple tile. Resizing the window should make its position relative to this inner box stay the same.</div>
+  </div>
+
+ </body>
+</html>