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+<!DOCTYPE HTML>
+<html>
+<!--
+Bug 1171489 - Tests if the framerate actor does not record timestamps from multiple frames.
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Framerate actor test</title>
+  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="application/javascript" src="inspector-helpers.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css">
+</head>
+<body>
+<pre id="test">
+<script>
+"use strict";
+
+window.onload = async function() {
+  // inspector-helpers doesnt wait for explicit finish
+  SimpleTest.waitForExplicitFinish();
+
+  const TICK = 1000;
+  const url = document.getElementById("testContent").href;
+  const { target, doc } = await attachURL(url);
+  const contentWin = doc.defaultView;
+
+  const front = await target.getFront("framerate");
+
+  await front.startRecording();
+  await waitFor(TICK);
+  const onWindowReady = waitForWindowReady();
+  contentWin.location.reload();
+
+  // Wait for the iframe to be loaded again
+  await onWindowReady;
+  await waitFor(TICK);
+  const ticks = await front.stopRecording();
+  await onRecordingStopped(ticks);
+
+  await target.destroy();
+  SimpleTest.finish();
+};
+
+// Local Helpers
+function waitFor(time) {
+  return new Promise(resolve => setTimeout(resolve, time));
+}
+
+function waitForWindowReady() {
+  return new Promise(resolve => {
+    window.addEventListener("message", function loaded(event) {
+      if (event.data === "ready") {
+        window.removeEventListener("message", loaded);
+        resolve();
+      }
+    });
+  });
+}
+
+function onRecordingStopped(ticks) {
+  const diffs = [];
+
+  info(`Got ${ticks.length} ticks.`);
+
+  for (let i = 1; i < ticks.length; i++) {
+    const prev = ticks[i - 1];
+    const curr = ticks[i];
+    diffs.push(curr - prev);
+    info(curr + " - " + (curr - prev));
+  }
+
+  // 1000 / 60 => 16.666... so we shouldn't get more than diffs of 16.66.. but
+  // when we get ticks from other frames they're usually at diffs of < 1. Sometimes
+  // ticks can still be less than 16ms even on one frame (usually following a very slow
+  // frame), so use a low number (2) to be our threshold
+  const THRESHOLD = 2;
+  ok(ticks.length >= 20,
+     "we should have atleast 20 ticks over the course of two seconds.");
+  const belowThreshold = diffs.filter(v => v <= THRESHOLD);
+  ok(belowThreshold.length <= 10,
+     "we should have very few frames less than the threshold");
+}
+</script>
+</pre>
+<a id="testContent" target="_blank" href="inspector-traversal-data.html">Test Document</a>
+</body>
+</html>