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diff --git a/testing/web-platform/tests/hr-time/test_cross_frame_start.html b/testing/web-platform/tests/hr-time/test_cross_frame_start.html
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+++ b/testing/web-platform/tests/hr-time/test_cross_frame_start.html
@@ -0,0 +1,59 @@
+<!DOCTYPE html>
+<html>
+  <head>
+        <meta charset="utf-8" >
+        <title>window.performance.now across frames</title>
+        <link rel="author" title="Google" href="http://www.google.com/">
+        <link rel="help" href="http://www.w3.org/TR/hr-time/#sec-extenstions-performance-interface">
+
+        <script src="/resources/testharness.js"></script>
+        <script src="/resources/testharnessreport.js"></script>
+
+        <script type="text/javascript">
+            setup({explicit_done: true});
+
+            var setup_frame = async_test("Setup the frame");
+
+            function start_test() {
+              setup_frame.step_timeout(function () {
+                var iframe = document.createElement('iframe');
+                iframe.id = 'frameContext';
+                iframe.onload = finish_test;
+                iframe.src = "resources/now_frame.html";
+                document.body.appendChild(iframe);
+                setup_frame.done();
+              }, 1000);
+            }
+
+            function finish_test() {
+              var childWindow = document.getElementById('frameContext').contentWindow;
+
+              // Verify a positive number is returned for both the frame and parent.
+              test(function() { assert_true(window.performance.now() > 0); }, 'parent performance.now() > 0');
+              test(function() { assert_true(childWindow.performance.now() > 0); }, 'child performance.now() > 0');
+
+              // Verify that the test properly created the child at least a second after the parent.
+              test(function () { assert_true(childWindow.performance.timing.navigationStart > (window.performance.timing.navigationStart + 1000)); },
+                                'Child created at least 1 second after parent');
+
+              test(function () {
+                var parentNow = window.performance.now();
+                var childNow = childWindow.performance.now();
+                var childParentSkew = Math.abs(childNow - parentNow);
+                assert_true(childParentSkew > 1000, 'Child and parent\'s now()s have different bases (skewed more than 1 second)');
+
+                var childLoadTime = childWindow.performance.timing.loadEventStart - childWindow.performance.timing.navigationStart;
+                assert_true(1000 > (childNow - childLoadTime), 'Child\'s now() is based on its document\'s navigationStart');
+              }, 'Child and parent time bases are correct');
+
+              done();
+            }
+        </script>
+
+    </head>
+    <body onload="start_test()">
+        <h1>Description</h1>
+        <p>This test validates the values of the window.performance.now() are based on the current document's navigationStart.</p>
+        <div id="log"></div>
+    </body>
+</html>