11 files changed, 975 insertions, 0 deletions
diff --git a/dom/media/test/browser/browser.ini b/dom/media/test/browser/browser.ini
new file mode 100644
index 0000000000..11ff9bad1c
--- /dev/null
+++ b/dom/media/test/browser/browser.ini
@@ -0,0 +1,28 @@
+[DEFAULT]
+subsuite = media-bc
+prefs =
+  gfx.font_loader.delay=0
+
+support-files =
+  file_empty_page.html
+  file_media.html
+  ../av1.mp4
+  ../bipbop_short_vp8.webm
+  ../bunny_hd_5s.mp4
+  ../eme_standalone.js
+  ../gizmo.mp4
+  ../gizmo.webm
+  ../sintel-short-clearkey-subsample-encrypted-video.webm
+  ../small-shot.flac
+  ../small-shot.m4a
+  ../small-shot.mp3
+  ../small-shot.ogg
+  ../TestPatternHDR.mp4
+
+[browser_encrypted_play_time_telemetry.js]
+skip-if =
+  apple_silicon # Disabled due to bleedover with other tests when run in regular suites; passes in "failures" jobs
+[browser_tab_visibility_and_play_time.js]
+skip-if =
+  os == "win" && os_version == "6.1" # Skip on Azure - frequent failure
+[browser_telemetry_video_hardware_decoding_support.js]
diff --git a/dom/media/test/browser/browser_encrypted_play_time_telemetry.js b/dom/media/test/browser/browser_encrypted_play_time_telemetry.js
new file mode 100644
index 0000000000..aebc386e6b
--- /dev/null
+++ b/dom/media/test/browser/browser_encrypted_play_time_telemetry.js
@@ -0,0 +1,266 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// This test verifies that telemetry gathered around encrypted media playtime
+// is gathered as expected.
+
+"use strict";
+
+/* import-globals-from ../eme_standalone.js */
+
+// Clears any existing telemetry data that has been accumulated. Returns a
+// promise the will be resolved once the telemetry store is clear.
+async function clearTelemetry() {
+  // There's an arbitrary interval of 2 seconds in which the content
+  // processes sync their event data with the parent process, we wait
+  // this out to ensure that we clear everything that is left over from
+  // previous tests and don't receive random events in the middle of our tests.
+  // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+  await new Promise(resolve => setTimeout(resolve, 2000));
+
+  Services.telemetry.clearEvents();
+  return TestUtils.waitForCondition(() => {
+    let events = Services.telemetry.snapshotEvents(
+      Ci.nsITelemetry.DATASET_ALL_CHANNELS,
+      true
+    ).content;
+    return !events || !events.length;
+  });
+}
+
+// Opens a tab containing a blank page, returns a promise that will resolve
+// to that tab.
+async function openTab() {
+  const emptyPageUri =
+    "https://example.com/browser/dom/media/test/browser/file_empty_page.html";
+  return BrowserTestUtils.openNewForegroundTab(window.gBrowser, emptyPageUri);
+}
+
+// Creates and configures a video element for EME playback in `tab`. Does not
+// start playback for the element. Returns a promise that will resolve once
+// the element is setup and ready for playback.
+async function loadEmeVideo(tab) {
+  const emeHelperUri =
+    gTestPath.substr(0, gTestPath.lastIndexOf("/")) + "/eme_standalone.js";
+  return SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [emeHelperUri],
+    async _emeHelperUri => {
+      // Begin helper functions.
+      async function once(target, name) {
+        return new Promise(r =>
+          target.addEventListener(name, r, { once: true })
+        );
+      }
+
+      // Helper to clone data into content so the EME helper can use the data.
+      function cloneIntoContent(data) {
+        return Cu.cloneInto(data, content.wrappedJSObject);
+      }
+      // End helper functions.
+
+      // Load the EME helper into content.
+      Services.scriptloader.loadSubScript(_emeHelperUri, content);
+      // Setup EME with the helper.
+      let video = content.document.createElement("video");
+      video.id = "media";
+      content.document.body.appendChild(video);
+      let emeHelper = new content.wrappedJSObject.EmeHelper();
+      emeHelper.SetKeySystem(
+        content.wrappedJSObject.EmeHelper.GetClearkeyKeySystemString()
+      );
+      emeHelper.SetInitDataTypes(cloneIntoContent(["webm"]));
+      emeHelper.SetVideoCapabilities(
+        cloneIntoContent([{ contentType: 'video/webm; codecs="vp9"' }])
+      );
+      emeHelper.AddKeyIdAndKey(
+        "2cdb0ed6119853e7850671c3e9906c3c",
+        "808b9adac384de1e4f56140f4ad76194"
+      );
+      emeHelper.onerror = error => {
+        is(false, `Got unexpected error from EME helper: ${error}`);
+      };
+      await emeHelper.ConfigureEme(video);
+      // Done setting up EME.
+
+      // Setup MSE.
+      const ms = new content.wrappedJSObject.MediaSource();
+      video.src = content.wrappedJSObject.URL.createObjectURL(ms);
+      await once(ms, "sourceopen");
+      const sb = ms.addSourceBuffer("video/webm");
+      const videoFile = "sintel-short-clearkey-subsample-encrypted-video.webm";
+      let fetchResponse = await content.fetch(videoFile);
+      sb.appendBuffer(await fetchResponse.arrayBuffer());
+      await once(sb, "updateend");
+      ms.endOfStream();
+      await once(ms, "sourceended");
+    }
+  );
+}
+
+// Plays the media in `tab` until the 'ended' event is fire. Returns a promise
+// that resolves once that state has been reached.
+async function playMediaThrough(tab) {
+  return SpecialPowers.spawn(tab.linkedBrowser, [], async () => {
+    let video = content.document.getElementById("media");
+    await Promise.all([new Promise(r => (video.onended = r)), video.play()]);
+  });
+}
+
+// Plays the media in `tab` until the 'timeupdate' event is fire. Returns a
+// promise that resolves once that state has been reached.
+async function playMediaToTimeUpdate(tab) {
+  return SpecialPowers.spawn(tab.linkedBrowser, [], async () => {
+    let video = content.document.getElementById("media");
+    await Promise.all([
+      new Promise(r => (video.ontimeupdate = r)),
+      video.play(),
+    ]);
+  });
+}
+
+// Aborts existing loads and replaces the media on the media element with an
+// unencrypted file.
+async function replaceMediaWithUnencrypted(tab) {
+  return SpecialPowers.spawn(tab.linkedBrowser, [], async () => {
+    let video = content.document.getElementById("media");
+    video.src = "gizmo.mp4";
+    video.load();
+  });
+}
+
+// Clears/nulls the media keys on the media in `tab`.
+async function clearMediaKeys(tab) {
+  return SpecialPowers.spawn(tab.linkedBrowser, [], async () => {
+    let video = content.document.getElementById("media");
+    await video.setMediaKeys(null);
+  });
+}
+
+// Wait for telemetry information to be received from the content process
+// then get the relevant histograms for the tests and return the sums of
+// those histograms. If a histogram does not exist this will return a 0
+// sum. Returns a promise the resolves to an object with sums for
+// - VIDEO_PLAY_TIME_MS
+// - VIDEO_ENCRYPTED_PLAY_TIME_MS
+// - VIDEO_CLEARKEY_PLAY_TIME_MS
+// This function clears the histograms as it gets them.
+async function getTelemetrySums() {
+  // The telemetry was gathered in the content process, so we have to wait
+  // until is arrived in the parent to check it. At time of writing there's
+  // not a more elegant way of doing this than polling.
+  return TestUtils.waitForCondition(() => {
+    let histograms = Services.telemetry.getSnapshotForHistograms(
+      "main",
+      true
+    ).content;
+    // All the histogram data should come at the same time, so we just check
+    // for playtime here as we always expect it in these tests, but we'll
+    // grab other values if present.
+    if (histograms.VIDEO_PLAY_TIME_MS) {
+      // We only expect to have one value for each histogram, so returning the
+      // sums is a short hand for returning that one value.
+      return {
+        VIDEO_PLAY_TIME_MS: histograms.VIDEO_PLAY_TIME_MS.sum,
+        VIDEO_ENCRYPTED_PLAY_TIME_MS: histograms.VIDEO_ENCRYPTED_PLAY_TIME_MS
+          ? histograms.VIDEO_ENCRYPTED_PLAY_TIME_MS.sum
+          : 0,
+        VIDEO_CLEARKEY_PLAY_TIME_MS: histograms.VIDEO_CLEARKEY_PLAY_TIME_MS
+          ? histograms.VIDEO_CLEARKEY_PLAY_TIME_MS.sum
+          : 0,
+      };
+    }
+    return null;
+  }, "recorded telemetry from playing media");
+}
+
+// Clear telemetry before other tests. Internally the tests clear the telemetry
+// when they check it, so we shouldn't need to do this between tests.
+add_task(clearTelemetry);
+
+add_task(async function testEncryptedMediaPlayback() {
+  let testTab = await openTab();
+
+  await loadEmeVideo(testTab);
+  await playMediaThrough(testTab);
+
+  BrowserTestUtils.removeTab(testTab);
+
+  let telemetrySums = await getTelemetrySums();
+
+  ok(telemetrySums, "Should get play time telemetry");
+  is(
+    telemetrySums.VIDEO_PLAY_TIME_MS,
+    telemetrySums.VIDEO_ENCRYPTED_PLAY_TIME_MS,
+    "Play time should be the same as encrypted play time"
+  );
+  is(
+    telemetrySums.VIDEO_PLAY_TIME_MS,
+    telemetrySums.VIDEO_CLEARKEY_PLAY_TIME_MS,
+    "Play time should be the same as clearkey play time"
+  );
+  ok(
+    telemetrySums.VIDEO_PLAY_TIME_MS > 0,
+    "Should have a play time greater than zero"
+  );
+});
+
+add_task(async function testChangingFromEncryptedToUnencrypted() {
+  let testTab = await openTab();
+
+  await loadEmeVideo(testTab);
+  await replaceMediaWithUnencrypted(testTab);
+  await playMediaToTimeUpdate(testTab);
+
+  BrowserTestUtils.removeTab(testTab);
+
+  let telemetrySums = await getTelemetrySums();
+
+  ok(telemetrySums, "Should get play time telemetry");
+  is(
+    telemetrySums.VIDEO_ENCRYPTED_PLAY_TIME_MS,
+    0,
+    "Encrypted play time should be 0"
+  );
+  is(
+    telemetrySums.VIDEO_PLAY_TIME_MS,
+    telemetrySums.VIDEO_CLEARKEY_PLAY_TIME_MS,
+    "Play time should be the same as clearkey play time because the media element still has a media keys attached"
+  );
+  ok(
+    telemetrySums.VIDEO_PLAY_TIME_MS > 0,
+    "Should have a play time greater than zero"
+  );
+});
+
+add_task(
+  async function testChangingFromEncryptedToUnencryptedAndClearingMediaKeys() {
+    let testTab = await openTab();
+
+    await loadEmeVideo(testTab);
+    await replaceMediaWithUnencrypted(testTab);
+    await clearMediaKeys(testTab);
+    await playMediaToTimeUpdate(testTab);
+
+    BrowserTestUtils.removeTab(testTab);
+
+    let telemetrySums = await getTelemetrySums();
+
+    ok(telemetrySums, "Should get play time telemetry");
+    is(
+      telemetrySums.VIDEO_ENCRYPTED_PLAY_TIME_MS,
+      0,
+      "Encrypted play time should be 0"
+    );
+    is(
+      telemetrySums.VIDEO_CLEARKEY_PLAY_TIME_MS,
+      0,
+      "Clearkey play time should be 0"
+    );
+    ok(
+      telemetrySums.VIDEO_PLAY_TIME_MS > 0,
+      "Should have a play time greater than zero"
+    );
+  }
+);
diff --git a/dom/media/test/browser/browser_tab_visibility_and_play_time.js b/dom/media/test/browser/browser_tab_visibility_and_play_time.js
new file mode 100644
index 0000000000..66fae40889
--- /dev/null
+++ b/dom/media/test/browser/browser_tab_visibility_and_play_time.js
@@ -0,0 +1,216 @@
+/**
+ * This test is used to ensure that invisible play time would be accumulated
+ * when tab is in background. It also checks the HDR video accumulation time.
+ * However, this test won't directly check the reported telemetry result,
+ * because we can't check the snapshot histogram in the content process.
+ * The actual probe checking happens in `test_accumulated_play_time.html`.
+ */
+"use strict";
+
+const PAGE_URL =
+  "https://example.com/browser/dom/media/test/browser/file_media.html";
+
+// This HDR tests will only pass on platforms that accurately report color
+// depth in their VideoInfo structures. Presently, that is only true for
+// macOS.
+
+const reportsColorDepthFromVideoData = AppConstants.platform == "macosx";
+
+add_task(async function testChangingTabVisibilityAffectsInvisiblePlayTime() {
+  const originalTab = gBrowser.selectedTab;
+  const mediaTab = await openMediaTab(PAGE_URL);
+
+  info(`measuring play time when tab is in foreground`);
+  await startMedia({
+    mediaTab,
+    shouldAccumulateTime: true,
+    shouldAccumulateInvisibleTime: false,
+    shouldAccumulateHDRTime: reportsColorDepthFromVideoData,
+  });
+  await pauseMedia(mediaTab);
+
+  info(`measuring play time when tab is in background`);
+  await BrowserTestUtils.switchTab(window.gBrowser, originalTab);
+  await startMedia({
+    mediaTab,
+    shouldAccumulateTime: true,
+    shouldAccumulateInvisibleTime: true,
+    shouldAccumulateHDRTime: reportsColorDepthFromVideoData,
+  });
+  await pauseMedia(mediaTab);
+
+  BrowserTestUtils.removeTab(mediaTab);
+});
+
+/**
+ * Following are helper functions.
+ */
+async function openMediaTab(url) {
+  info(`open tab for media playback`);
+  const tab = await BrowserTestUtils.openNewForegroundTab(window.gBrowser, url);
+  info(`add content helper functions and variables`);
+  await SpecialPowers.spawn(tab.linkedBrowser, [], _ => {
+    content.waitForOnTimeUpdate = element => {
+      return new Promise(resolve => {
+        element.addEventListener(
+          "timeupdate",
+          e => {
+            resolve();
+          },
+          { once: true }
+        );
+      });
+    };
+
+    content.sleep = ms => {
+      return new Promise(resolve => content.setTimeout(resolve, ms));
+    };
+
+    content.assertAttributeDefined = (videoChrome, checkType) => {
+      ok(videoChrome[checkType] != undefined, `${checkType} exists`);
+    };
+    content.assertValueEqualTo = (videoChrome, checkType, expectedValue) => {
+      content.assertAttributeDefined(videoChrome, checkType);
+      is(
+        videoChrome[checkType],
+        expectedValue,
+        `${checkType} equals to ${expectedValue}`
+      );
+    };
+    content.assertValueConstantlyIncreases = async (videoChrome, checkType) => {
+      content.assertAttributeDefined(videoChrome, checkType);
+      const valueSnapshot = videoChrome[checkType];
+      await content.waitForOnTimeUpdate(videoChrome);
+      ok(
+        videoChrome[checkType] > valueSnapshot,
+        `${checkType} keeps increasing`
+      );
+    };
+    content.assertValueKeptUnchanged = async (videoChrome, checkType) => {
+      content.assertAttributeDefined(videoChrome, checkType);
+      const valueSnapshot = videoChrome[checkType];
+      await content.sleep(1000);
+      ok(
+        videoChrome[checkType] == valueSnapshot,
+        `${checkType} keeps unchanged`
+      );
+    };
+  });
+  return tab;
+}
+
+function startMedia({
+  mediaTab,
+  shouldAccumulateTime,
+  shouldAccumulateInvisibleTime,
+  shouldAccumulateHDRTime,
+}) {
+  return SpecialPowers.spawn(
+    mediaTab.linkedBrowser,
+    [
+      shouldAccumulateTime,
+      shouldAccumulateInvisibleTime,
+      shouldAccumulateHDRTime,
+    ],
+    async (accumulateTime, accumulateInvisibleTime, accumulateHDRTime) => {
+      const video = content.document.getElementById("video");
+      ok(
+        await video.play().then(
+          () => true,
+          () => false
+        ),
+        "video started playing"
+      );
+      const videoChrome = SpecialPowers.wrap(video);
+      if (accumulateTime) {
+        await content.assertValueConstantlyIncreases(
+          videoChrome,
+          "totalVideoPlayTime"
+        );
+      } else {
+        await content.assertValueKeptUnchanged(
+          videoChrome,
+          "totalVideoPlayTime"
+        );
+      }
+      if (accumulateInvisibleTime) {
+        await content.assertValueConstantlyIncreases(
+          videoChrome,
+          "invisiblePlayTime"
+        );
+      } else {
+        await content.assertValueKeptUnchanged(
+          videoChrome,
+          "invisiblePlayTime"
+        );
+      }
+
+      const videoHDR = content.document.getElementById("videoHDR");
+
+      // HDR test video might not decode on all platforms, so catch
+      // the play() command and exit early in such a case. Failure to
+      // decode might manifest as a timeout, so add a rejection race
+      // to catch that.
+      let didDecode = true;
+      const playPromise = videoHDR.play().then(
+        () => true,
+        () => false
+      );
+      /* eslint-disable mozilla/no-arbitrary-setTimeout */
+      const tooSlowPromise = new Promise(resolve =>
+        setTimeout(() => {
+          info("videoHDR timed out.");
+          didDecode = false;
+          resolve(false);
+        }, 1000)
+      );
+      /* eslint-enable mozilla/no-arbitrary-setTimeout */
+
+      let didPlay = await Promise.race(playPromise, tooSlowPromise).catch(
+        err => {
+          info("videoHDR failed to decode with error: " + err.message);
+          didDecode = false;
+          return false;
+        }
+      );
+
+      if (!didDecode) {
+        return;
+      }
+
+      ok(didPlay, "videoHDR started playing");
+      const videoHDRChrome = SpecialPowers.wrap(videoHDR);
+      if (accumulateHDRTime) {
+        await content.assertValueConstantlyIncreases(
+          videoHDRChrome,
+          "totalVideoHDRPlayTime"
+        );
+      } else {
+        await content.assertValueKeptUnchanged(
+          videoHDRChrome,
+          "totalVideoHDRPlayTime"
+        );
+      }
+    }
+  );
+}
+
+function pauseMedia(tab) {
+  return SpecialPowers.spawn(tab.linkedBrowser, [], async _ => {
+    const video = content.document.getElementById("video");
+    video.pause();
+    ok(true, "video paused");
+    const videoChrome = SpecialPowers.wrap(video);
+    await content.assertValueKeptUnchanged(videoChrome, "totalVideoPlayTime");
+    await content.assertValueKeptUnchanged(videoChrome, "invisiblePlayTime");
+
+    const videoHDR = content.document.getElementById("videoHDR");
+    videoHDR.pause();
+    ok(true, "videoHDR paused");
+    const videoHDRChrome = SpecialPowers.wrap(videoHDR);
+    await content.assertValueKeptUnchanged(
+      videoHDRChrome,
+      "totalVideoHDRPlayTime"
+    );
+  });
+}
diff --git a/dom/media/test/browser/browser_telemetry_video_hardware_decoding_support.js b/dom/media/test/browser/browser_telemetry_video_hardware_decoding_support.js
new file mode 100644
index 0000000000..3b1b41c03f
--- /dev/null
+++ b/dom/media/test/browser/browser_telemetry_video_hardware_decoding_support.js
@@ -0,0 +1,106 @@
+/**
+ * This test is used to ensure that the scalar which indicates whether hardware
+ * decoding is supported for a specific video codec type can be recorded
+ * correctly.
+ */
+"use strict";
+
+add_task(async function setupTestingPref() {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      // In order to test av1 in the chrome process, see https://bit.ly/3oF0oan
+      ["media.rdd-process.enabled", false],
+    ],
+  });
+});
+
+const ALL_SCALAR = "media.video_hardware_decoding_support";
+const HD_SCALAR = "media.video_hd_hardware_decoding_support";
+
+add_task(async function testVideoCodecs() {
+  // There are still other video codecs, but we only care about these popular
+  // codec types.
+  const testFiles = [
+    { fileName: "gizmo.mp4", type: "video/avc" },
+    { fileName: "gizmo.webm", type: "video/vp9" },
+    { fileName: "bipbop_short_vp8.webm", type: "video/vp8" },
+    { fileName: "av1.mp4", type: "video/av1" },
+    { fileName: "bunny_hd_5s.mp4", type: "video/avc", hd: true },
+  ];
+
+  for (const file of testFiles) {
+    const { fileName, type, hd } = file;
+    let video = document.createElement("video");
+    video.src = GetTestWebBasedURL(fileName);
+    await video.play();
+    let snapshot = Services.telemetry.getSnapshotForKeyedScalars(
+      "main",
+      false
+    ).parent;
+    ok(
+      snapshot.hasOwnProperty(ALL_SCALAR),
+      `Found stored scalar '${ALL_SCALAR}'`
+    );
+    ok(
+      snapshot[ALL_SCALAR].hasOwnProperty(type),
+      `Found key '${type}' in '${ALL_SCALAR}'`
+    );
+    if (hd) {
+      ok(
+        snapshot.hasOwnProperty(HD_SCALAR),
+        `HD video '${fileName}' should record a scalar '${HD_SCALAR}'`
+      );
+      ok(
+        snapshot[HD_SCALAR].hasOwnProperty(type),
+        `Found key '${type}' in '${HD_SCALAR}'`
+      );
+    } else {
+      ok(
+        !snapshot.hasOwnProperty(HD_SCALAR),
+        `SD video won't store a scalar '${HD_SCALAR}'`
+      );
+    }
+    video.src = "";
+    Services.telemetry.clearScalars();
+  }
+});
+
+add_task(async function testAudioCodecs() {
+  const testFiles = [
+    "small-shot.ogg",
+    "small-shot.m4a",
+    "small-shot.mp3",
+    "small-shot.flac",
+  ];
+  for (const file of testFiles) {
+    let audio = document.createElement("audio");
+    info(GetTestWebBasedURL(file));
+    audio.src = GetTestWebBasedURL(file);
+    await audio.play();
+    let snapshot = Services.telemetry.getSnapshotForKeyedScalars(
+      "main",
+      false
+    ).parent;
+    ok(
+      !snapshot ||
+        (!snapshot.hasOwnProperty(ALL_SCALAR) &&
+          !snapshot.hasOwnProperty(HD_SCALAR)),
+      `Did not record scalar for ${file}`
+    );
+    audio.src = "";
+  }
+});
+
+/**
+ * Return a web-based URL for a given file based on the testing directory.
+ * @param {String} fileName
+ *        file that caller wants its web-based url
+ */
+function GetTestWebBasedURL(fileName) {
+  return (
+    getRootDirectory(gTestPath).replace(
+      "chrome://mochitests/content",
+      "http://example.org"
+    ) + fileName
+  );
+}
diff --git a/dom/media/test/browser/file_empty_page.html b/dom/media/test/browser/file_empty_page.html
new file mode 100644
index 0000000000..cd1b7830be
--- /dev/null
+++ b/dom/media/test/browser/file_empty_page.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html>
+<html>
+<head>
+<title>An empty page</title>
+</head>
+<body>
+</body>
+</html>
diff --git a/dom/media/test/browser/file_media.html b/dom/media/test/browser/file_media.html
new file mode 100644
index 0000000000..36dca8d01c
--- /dev/null
+++ b/dom/media/test/browser/file_media.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html>
+<html>
+<head>
+<title>Non-Autoplay page</title>
+</head>
+<body>
+<video id="video" src="gizmo.mp4" loop></video>
+<video id="videoHDR" src="TestPatternHDR.mp4" loop></video>
+</body>
+</html>
diff --git a/dom/media/test/browser/wmfme/browser.ini b/dom/media/test/browser/wmfme/browser.ini
new file mode 100644
index 0000000000..9913bdb19e
--- /dev/null
+++ b/dom/media/test/browser/wmfme/browser.ini
@@ -0,0 +1,11 @@
+[DEFAULT]
+subsuite = media-bc
+tags = media-engine-compatible
+run-if = wmfme
+support-files =
+  head.js
+  file_video.html
+  ../../gizmo.mp4
+
+[browser_wmfme_crash.js]
+[browser_wmfme_max_crashes.js]
diff --git a/dom/media/test/browser/wmfme/browser_wmfme_crash.js b/dom/media/test/browser/wmfme/browser_wmfme_crash.js
new file mode 100644
index 0000000000..8ebe582595
--- /dev/null
+++ b/dom/media/test/browser/wmfme/browser_wmfme_crash.js
@@ -0,0 +1,52 @@
+"use strict";
+
+/**
+ * This test aims to ensure that the media engine playback will recover from a
+ * crash and keep playing without any problem.
+ */
+add_task(async function setupTestingPref() {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["media.wmf.media-engine.enabled", true],
+      ["media.wmf.media-engine.channel-decoder.enabled", true],
+    ],
+  });
+});
+
+const VIDEO_PAGE = GetTestWebBasedURL("file_video.html");
+
+add_task(async function testPlaybackRecoveryFromCrash() {
+  info(`Create a tab and load test page`);
+  let tab = await BrowserTestUtils.openNewForegroundTab(
+    window.gBrowser,
+    "about:blank"
+  );
+  BrowserTestUtils.loadURIString(tab.linkedBrowser, VIDEO_PAGE);
+  await BrowserTestUtils.browserLoaded(tab.linkedBrowser);
+
+  await playVideo(tab);
+
+  info("Ensure video is running via the media engine framework");
+  await assertRunningProcessAndDecoderName(tab, {
+    expectedProcess: "Utility MF Media Engine CDM",
+    expectedDecoder: "media engine video stream",
+  });
+
+  const pidBeforeCrash = await getMFCDMProcessId();
+  await crashUtilityProcess(pidBeforeCrash);
+
+  info("The CDM process should be recreated which makes media keep playing");
+  await assertRunningProcessAndDecoderName(tab, {
+    expectedProcess: "Utility MF Media Engine CDM",
+    expectedDecoder: "media engine video stream",
+  });
+
+  const pidAfterCrash = await getMFCDMProcessId();
+  isnot(
+    pidBeforeCrash,
+    pidAfterCrash,
+    `new process ${pidAfterCrash} is not previous crashed one ${pidBeforeCrash}`
+  );
+
+  BrowserTestUtils.removeTab(tab);
+});
diff --git a/dom/media/test/browser/wmfme/browser_wmfme_max_crashes.js b/dom/media/test/browser/wmfme/browser_wmfme_max_crashes.js
new file mode 100644
index 0000000000..4472814171
--- /dev/null
+++ b/dom/media/test/browser/wmfme/browser_wmfme_max_crashes.js
@@ -0,0 +1,69 @@
+"use strict";
+
+/**
+ * This test aims to ensure that the MFCDM process won't be recovered once the
+ * amount of crashes has exceeded the amount of value which we tolerate.
+ */
+add_task(async function setupTestingPref() {
+  await SpecialPowers.pushPrefEnv({
+    set: [
+      ["media.wmf.media-engine.enabled", true],
+      ["media.wmf.media-engine.channel-decoder.enabled", true],
+    ],
+  });
+});
+
+const VIDEO_PAGE = GetTestWebBasedURL("file_video.html");
+
+add_task(async function testPlaybackRecoveryFromCrash() {
+  const maxCrashes = Services.prefs.getIntPref(
+    "media.wmf.media-engine.max-crashes"
+  );
+  info(`The amount of tolerable crashes=${maxCrashes}`);
+
+  info(`Create a tab and load test page`);
+  let tab = await BrowserTestUtils.openNewForegroundTab(
+    window.gBrowser,
+    "about:blank"
+  );
+  BrowserTestUtils.loadURIString(tab.linkedBrowser, VIDEO_PAGE);
+  await BrowserTestUtils.browserLoaded(tab.linkedBrowser);
+
+  await playVideo(tab);
+
+  info("Ensure video is running via the media engine framework");
+  await assertRunningProcessAndDecoderName(tab, {
+    expectedProcess: "Utility MF Media Engine CDM",
+    expectedDecoder: "media engine video stream",
+  });
+
+  let pidBeforeCrash, pidAfterCrash;
+  for (let idx = 0; idx < maxCrashes; idx++) {
+    pidBeforeCrash = await getMFCDMProcessId();
+    await crashUtilityProcess(pidBeforeCrash);
+
+    info("The CDM process should be recreated which makes media keep playing");
+    await assertRunningProcessAndDecoderName(tab, {
+      expectedProcess: "Utility MF Media Engine CDM",
+      expectedDecoder: "media engine video stream",
+    });
+
+    pidAfterCrash = await getMFCDMProcessId();
+    isnot(
+      pidBeforeCrash,
+      pidAfterCrash,
+      `new process ${pidAfterCrash} is not previous crashed one ${pidBeforeCrash}`
+    );
+  }
+
+  info("This crash should result in not spawning MFCDM process again");
+  pidBeforeCrash = await getMFCDMProcessId();
+  await crashUtilityProcess(pidBeforeCrash);
+
+  await assertNotEqualRunningProcessAndDecoderName(tab, {
+    givenProcess: "Utility MF Media Engine CDM",
+    givenDecoder: "media engine video stream",
+  });
+
+  BrowserTestUtils.removeTab(tab);
+});
diff --git a/dom/media/test/browser/wmfme/file_video.html b/dom/media/test/browser/wmfme/file_video.html
new file mode 100644
index 0000000000..3c70268fbb
--- /dev/null
+++ b/dom/media/test/browser/wmfme/file_video.html
@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+<html>
+<head>
+<title>video</title>
+</head>
+<body>
+<video id="v" src="gizmo.mp4" controls loop></video>
+</body>
+</html>
diff --git a/dom/media/test/browser/wmfme/head.js b/dom/media/test/browser/wmfme/head.js
new file mode 100644
index 0000000000..2524287870
--- /dev/null
+++ b/dom/media/test/browser/wmfme/head.js
@@ -0,0 +1,200 @@
+"use strict";
+
+/**
+ * Return a web-based URL for a given file based on the testing directory.
+ * @param {String} fileName
+ *        file that caller wants its web-based url
+ * @param {Boolean} cors [optional]
+ *        if set, then return a url with different origin
+ */
+function GetTestWebBasedURL(fileName) {
+  const origin = "https://example.com";
+  return (
+    getRootDirectory(gTestPath).replace("chrome://mochitests/content", origin) +
+    fileName
+  );
+}
+
+/**
+ * Return current process Id for the Media Foundation CDM process.
+ */
+async function getMFCDMProcessId() {
+  const process = (await ChromeUtils.requestProcInfo()).children.find(
+    p =>
+      p.type === "utility" &&
+      p.utilityActors.find(a => a.actorName === "mfMediaEngineCDM")
+  );
+  return process.pid;
+}
+
+/**
+ * Make the utility process with given process id crash.
+ * @param {int} pid
+ *        the process id for the process which is going to crash
+ */
+async function crashUtilityProcess(utilityPid) {
+  info(`Crashing process ${utilityPid}`);
+  SimpleTest.expectChildProcessCrash();
+
+  const crashMan = Services.crashmanager;
+  const utilityProcessGone = TestUtils.topicObserved(
+    "ipc:utility-shutdown",
+    (subject, data) => {
+      info(`ipc:utility-shutdown: data=${data} subject=${subject}`);
+      return parseInt(data, 10) === utilityPid;
+    }
+  );
+
+  info("Prune any previous crashes");
+  const future = new Date(Date.now() + 1000 * 60 * 60 * 24);
+  await crashMan.pruneOldCrashes(future);
+
+  info("Crash Utility Process");
+  const ProcessTools = Cc["@mozilla.org/processtools-service;1"].getService(
+    Ci.nsIProcessToolsService
+  );
+
+  info(`Crash Utility Process ${utilityPid}`);
+  ProcessTools.crash(utilityPid);
+
+  info(`Waiting for utility process ${utilityPid} to go away.`);
+  let [subject, data] = await utilityProcessGone;
+  ok(
+    parseInt(data, 10) === utilityPid,
+    `Should match the crashed PID ${utilityPid} with ${data}`
+  );
+  ok(
+    subject instanceof Ci.nsIPropertyBag2,
+    "Subject needs to be a nsIPropertyBag2 to clean up properly"
+  );
+
+  const dumpID = subject.getPropertyAsAString("dumpID");
+  ok(dumpID, "There should be a dumpID");
+
+  await crashMan.ensureCrashIsPresent(dumpID);
+  await crashMan.getCrashes().then(crashes => {
+    is(crashes.length, 1, "There should be only one record");
+    const crash = crashes[0];
+    ok(
+      crash.isOfType(
+        crashMan.processTypes[Ci.nsIXULRuntime.PROCESS_TYPE_UTILITY],
+        crashMan.CRASH_TYPE_CRASH
+      ),
+      "Record should be a utility process crash"
+    );
+    ok(crash.id === dumpID, "Record should have an ID");
+  });
+
+  let minidumpDirectory = Services.dirsvc.get("ProfD", Ci.nsIFile);
+  minidumpDirectory.append("minidumps");
+
+  let dumpfile = minidumpDirectory.clone();
+  dumpfile.append(dumpID + ".dmp");
+  if (dumpfile.exists()) {
+    info(`Removal of ${dumpfile.path}`);
+    dumpfile.remove(false);
+  }
+
+  let extrafile = minidumpDirectory.clone();
+  extrafile.append(dumpID + ".extra");
+  info(`Removal of ${extrafile.path}`);
+  if (extrafile.exists()) {
+    extrafile.remove(false);
+  }
+}
+
+/**
+ * Make video in the tab play.
+ * @param {object} tab
+ *        the tab contains at least one video element
+ */
+async function playVideo(tab) {
+  return SpecialPowers.spawn(tab.linkedBrowser, [], async _ => {
+    const video = content.document.querySelector("video");
+    ok(
+      await video.play().then(
+        () => true,
+        () => false
+      ),
+      "video started playing"
+    );
+  });
+}
+
+/**
+ * Check whether the video playback is performed in the right process and right decoder.
+ * @param {object} tab
+ *        the tab which has a playing video
+ * @param {string} expectedProcess
+ *        the expected process name
+ * @param {string} expectedDecoder
+ *        the expected decoder name
+ */
+async function assertRunningProcessAndDecoderName(
+  tab,
+  { expectedProcess, expectedDecoder } = {}
+) {
+  return SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [expectedProcess, expectedDecoder],
+    // eslint-disable-next-line no-shadow
+    async (expectedProcess, expectedDecoder) => {
+      const video = content.document.querySelector("video");
+      ok(!video.paused, "checking a playing video");
+
+      const debugInfo = await SpecialPowers.wrap(video).mozRequestDebugInfo();
+      const videoDecoderName = debugInfo.decoder.reader.videoDecoderName;
+
+      const isExpectedDecoder =
+        videoDecoderName.indexOf(`${expectedDecoder}`) == 0;
+      ok(
+        isExpectedDecoder,
+        `Playback running by decoder '${videoDecoderName}', expected '${expectedDecoder}'`
+      );
+
+      const isExpectedProcess =
+        videoDecoderName.indexOf(`(${expectedProcess} remote)`) > 0;
+      ok(
+        isExpectedProcess,
+        `Playback running in process '${videoDecoderName}', expected '${expectedProcess}'`
+      );
+    }
+  );
+}
+
+/**
+ * Check whether the video playback is not performed in the given process and given decoder.
+ * @param {object} tab
+ *        the tab which has a playing video
+ * @param {string} givenProcess
+ *        the process name on which the video playback should not be running
+ * @param {string} givenDecoder
+ *        the decoder name with which the video playback should not be running
+ */
+async function assertNotEqualRunningProcessAndDecoderName(
+  tab,
+  { givenProcess, givenDecoder } = {}
+) {
+  return SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [givenProcess, givenDecoder],
+    // eslint-disable-next-line no-shadow
+    async (givenProcess, givenDecoder) => {
+      const video = content.document.querySelector("video");
+      ok(!video.paused, "checking a playing video");
+
+      const debugInfo = await SpecialPowers.wrap(video).mozRequestDebugInfo();
+      const videoDecoderName = debugInfo.decoder.reader.videoDecoderName;
+      const pattern = /(.+?)\s+\((\S+)\s+remote\)/;
+      const match = videoDecoderName.match(pattern);
+      if (match) {
+        const decoder = match[1];
+        const process = match[2];
+        isnot(decoder, givenDecoder, `Decoder name is not equal`);
+        isnot(process, givenProcess, `Process name is not equal`);
+      } else {
+        ok(false, "failed to match decoder/process name?");
+      }
+    }
+  );
+}