--- a/testing/web-platform/meta/MANIFEST.json
+++ b/testing/web-platform/meta/MANIFEST.json
@@ -354752,22 +354752,16 @@
     ]
    ],
    "web-animations/interfaces/AnimationEffectTiming/getAnimations.html": [
     [
      "/web-animations/interfaces/AnimationEffectTiming/getAnimations.html",
      {}
     ]
    ],
-   "web-animations/interfaces/AnimationEffectTiming/getComputedStyle.html": [
-    [
-     "/web-animations/interfaces/AnimationEffectTiming/getComputedStyle.html",
-     {}
-    ]
-   ],
    "web-animations/interfaces/AnimationEffectTiming/idlharness.html": [
     [
      "/web-animations/interfaces/AnimationEffectTiming/idlharness.html",
      {}
     ]
    ],
    "web-animations/interfaces/AnimationEffectTiming/iterationStart.html": [
     [
@@ -585892,21 +585886,21 @@
    "177a2f3e9dd366bfe4661c160cc23b73c27dec20",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/delay.html": [
    "e2b0cf3709d9b886f058a13d2a8fa467ab7fd1b4",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/direction.html": [
-   "ae9a1a3b2a5ae8dde6c0d2a7f2acad0fa93d6d5e",
+   "99c67afe9b67b8ad2277ba788acecd2b4f53f7c7",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/duration.html": [
-   "025375526e36809bad4766de22f0ab24e4378a21",
+   "68b2a5f5d382c50c93d05b7692b41b31dc891d3a",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/easing.html": [
    "26bc80cba1202beeb4d19115fcea0838a104ae9a",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/endDelay.html": [
    "0c4e2cfee8ecb4fb7879df6c85ba0ba38310662d",
@@ -585915,30 +585909,26 @@
   "web-animations/interfaces/AnimationEffectTiming/fill.html": [
    "c0237dd37bd3e56e32bd3e027c5f9357081cfef0",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/getAnimations.html": [
    "e0ad6da869693c4e4b57aa2e5e3cb4ec557c7bc8",
    "testharness"
   ],
-  "web-animations/interfaces/AnimationEffectTiming/getComputedStyle.html": [
-   "201bac6d13f4f8ed556fe63df214d6d565ba94b7",
-   "testharness"
-  ],
   "web-animations/interfaces/AnimationEffectTiming/idlharness.html": [
    "a4e72d3ebf93a0bb6934f887c3da250a2ab67b63",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/iterationStart.html": [
    "c4d40ffdd9080732f202d9067f901cc065c470de",
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffectTiming/iterations.html": [
-   "e906c84dc4774846387eb9ea89d6707cee84dccb",
+   "739a1f8f83d3336af9e58d4b2914302a3907e2db",
    "testharness"
   ],
   "web-animations/interfaces/AnimationPlaybackEvent/constructor.html": [
    "1bc5f4dda96078a08a4b06ab0f6bf7b10e0acce3",
    "testharness"
   ],
   "web-animations/interfaces/AnimationPlaybackEvent/idlharness.html": [
    "37bd201a374913d0cd580b89b07688b5b655776d",

--- a/testing/web-platform/tests/web-animations/interfaces/AnimationEffectTiming/direction.html
+++ b/testing/web-platform/tests/web-animations/interfaces/AnimationEffectTiming/direction.html
@@ -22,10 +22,87 @@ test(function(t) {
   var directions = ['normal', 'reverse', 'alternate', 'alternate-reverse'];
   directions.forEach(function(direction) {
     anim.effect.timing.direction = direction;
     assert_equals(anim.effect.timing.direction, direction,
                   'set direction to ' + direction);
   });
 }, 'Can be set to each of the possible keywords');
 
+test(function(t) {
+  var div = createDiv(t);
+  var anim = div.animate(null, { duration: 10000, direction: 'normal' });
+  anim.currentTime = 7000;
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0.7,
+                     'progress before updating direction');
+
+  anim.effect.timing.direction = 'reverse';
+
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0.3,
+                     'progress after updating direction');
+}, 'Can be changed from \'normal\' to \'reverse\' while in progress');
+
+test(function(t) {
+  var div = createDiv(t);
+  var anim = div.animate({ opacity: [ 0, 1 ] },
+                         { duration: 10000,
+                           direction: 'normal' });
+  assert_equals(anim.effect.getComputedTiming().progress, 0,
+                'progress before updating direction');
+
+  anim.effect.timing.direction = 'reverse';
+
+  assert_equals(anim.effect.getComputedTiming().progress, 1,
+                'progress after updating direction');
+}, 'Can be changed from \'normal\' to \'reverse\' while at start of active'
+   + ' interval');
+
+test(function(t) {
+  var div = createDiv(t);
+  var anim = div.animate({ opacity: [ 0, 1 ] },
+                         { fill: 'backwards',
+                           duration: 10000,
+                           delay: 10000,
+                           direction: 'normal' });
+  assert_equals(anim.effect.getComputedTiming().progress, 0,
+                'progress before updating direction');
+
+  anim.effect.timing.direction = 'reverse';
+
+  assert_equals(anim.effect.getComputedTiming().progress, 1,
+                'progress after updating direction');
+}, 'Can be changed from \'normal\' to \'reverse\' while filling backwards');
+
+test(function(t) {
+  var div = createDiv(t);
+  var anim = div.animate({ opacity: [ 0, 1 ] },
+                         { iterations: 2,
+                           duration: 10000,
+                           direction: 'normal' });
+  anim.currentTime = 17000;
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0.7,
+                     'progress before updating direction');
+
+  anim.effect.timing.direction = 'alternate';
+
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0.3,
+                     'progress after updating direction');
+}, 'Can be changed from \'normal\' to \'alternate\' while in progress');
+
+test(function(t) {
+  var div = createDiv(t);
+  var anim = div.animate({ opacity: [ 0, 1 ] },
+                         { iterations: 2,
+                           duration: 10000,
+                           direction: 'alternate' });
+  anim.currentTime = 17000;
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0.3,
+                     'progress before updating direction');
+
+  anim.effect.timing.direction = 'alternate-reverse';
+
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0.7,
+                     'progress after updating direction');
+}, 'Can be changed from \'alternate\' to \'alternate-reverse\' while in'
+   + ' progress');
+
 </script>
 </body>

--- a/testing/web-platform/tests/web-animations/interfaces/AnimationEffectTiming/duration.html
+++ b/testing/web-platform/tests/web-animations/interfaces/AnimationEffectTiming/duration.html
@@ -164,10 +164,27 @@ promise_test(function(t) {
                        'startTime should be unaffected by changing effect ' +
                        'duration');
     assert_times_equal(anim.currentTime, originalCurrentTime,
                        'currentTime should be unaffected by changing effect ' +
                        'duration');
   });
 }, 'Extending an effect\'s duration does not change the start or current time');
 
+test(function(t) {
+  var div = createDiv(t);
+  var anim = div.animate(null, { duration: 100000, fill: 'both' });
+  anim.finish();
+  assert_equals(anim.effect.getComputedTiming().progress, 1,
+                'progress when animation is finished');
+  anim.effect.timing.duration *= 2;
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0.5,
+                     'progress after doubling the duration');
+  anim.effect.timing.duration = 0;
+  assert_equals(anim.effect.getComputedTiming().progress, 1,
+                'progress after setting duration to zero');
+  anim.effect.timing.duration = 'auto';
+  assert_equals(anim.effect.getComputedTiming().progress, 1,
+                'progress after setting duration to \'auto\'');
+}, 'Can be updated while the animation is in progress');
+
 </script>
 </body>

deleted file mode 100644
--- a/testing/web-platform/tests/web-animations/interfaces/AnimationEffectTiming/getComputedStyle.html
+++ /dev/null
@@ -1,171 +0,0 @@
-<!DOCTYPE html>
-<meta charset=utf-8>
-<title>getComputedStyle</title>
-<link rel="help" href="http://w3c.github.io/web-animations/#animationeffecttiming">
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="../../testcommon.js"></script>
-<body>
-<div id="log"></div>
-<script>
-'use strict';
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 0, 1 ] }, 100000);
-  anim.finish();
-  assert_equals(getComputedStyle(div).opacity, '1', 'animation finished');
-  anim.effect.timing.duration *= 2;
-  assert_equals(getComputedStyle(div).opacity, '0.5', 'set double duration');
-  anim.effect.timing.duration = 0;
-  assert_equals(getComputedStyle(div).opacity, '1', 'set duration 0');
-  anim.effect.timing.duration = 'auto';
-  assert_equals(getComputedStyle(div).opacity, '1', 'set duration \'auto\'');
-}, 'changed duration immediately updates its computed styles');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 0, 1 ] }, 100000);
-  anim.finish();
-  assert_equals(getComputedStyle(div).opacity, '1', 'animation finished');
-  anim.effect.timing.iterations = 2;
-  assert_equals(getComputedStyle(div).opacity, '0', 'set 2 iterations');
-  anim.effect.timing.iterations = 0;
-  assert_equals(getComputedStyle(div).opacity, '1', 'set iterations 0');
-  anim.effect.timing.iterations = Infinity;
-  assert_equals(getComputedStyle(div).opacity, '0', 'set iterations Infinity');
-}, 'changed iterations immediately updates its computed styles');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 1, 0 ] },
-                         { duration: 10000, endDelay: 1000, fill: 'none' });
-
-  anim.currentTime = 9000;
-  assert_equals(getComputedStyle(div).opacity, '0.1',
-                'set currentTime during duration');
-
-  anim.currentTime = 10900;
-  assert_equals(getComputedStyle(div).opacity, '1',
-                'set currentTime during endDelay');
-
-  anim.currentTime = 11100;
-  assert_equals(getComputedStyle(div).opacity, '1',
-                'set currentTime after endDelay');
-}, 'change currentTime when fill is none and endDelay is positive');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 1, 0 ] },
-                         { duration: 10000,
-                           endDelay: 1000,
-                           fill: 'forwards' });
-  anim.currentTime = 5000;
-  assert_equals(getComputedStyle(div).opacity, '0.5',
-                'set currentTime during duration');
-
-  anim.currentTime = 9999;
-  assert_equals(getComputedStyle(div).opacity, '0.0001',
-                'set currentTime just a little before duration');
-
-  anim.currentTime = 10900;
-  assert_equals(getComputedStyle(div).opacity, '0',
-                'set currentTime during endDelay');
-
-  anim.currentTime = 11100;
-  assert_equals(getComputedStyle(div).opacity, '0',
-                'set currentTime after endDelay');
-}, 'change currentTime when fill forwards and endDelay is positive');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 1, 0 ] },
-                         { duration: 10000, endDelay: -5000, fill: 'none' });
-
-  anim.currentTime = 1000;
-  assert_equals(getComputedStyle(div).opacity, '0.9',
-                'set currentTime before endTime');
-
-  anim.currentTime = 10000;
-  assert_equals(getComputedStyle(div).opacity, '1',
-                'set currentTime after endTime');
-}, 'change currentTime when fill none and endDelay is negative');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 1, 0 ] },
-                         { duration: 10000,
-                           endDelay: -5000,
-                           fill: 'forwards' });
-
-  anim.currentTime = 1000;
-  assert_equals(getComputedStyle(div).opacity, '0.9',
-                'set currentTime before endTime');
-
-  anim.currentTime = 5000;
-  assert_equals(getComputedStyle(div).opacity, '0.5',
-                'set currentTime same as endTime');
-
-  anim.currentTime = 10000;
-  assert_equals(getComputedStyle(div).opacity, '0',
-                'set currentTime after endTime');
-}, 'change currentTime when fill forwards and endDelay is negative');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 0, 1 ] },
-                         { duration: 10000,
-                           direction: 'normal' });
-
-  anim.currentTime = 7000;
-  anim.effect.timing.direction = 'reverse';
-
-  assert_equals(getComputedStyle(div).opacity, '0.3',
-                'change direction from "normal" to "reverse"');
-}, 'change direction from "normal" to "reverse"');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 0, 1 ] },
-                         { iterations: 2,
-                           duration: 10000,
-                           direction: 'normal' });
-
-  anim.currentTime = 17000;
-  anim.effect.timing.direction = 'alternate';
-
-  assert_equals(getComputedStyle(div).opacity, '0.3',
-                'change direction from "normal" to "alternate"');
-  }, 'change direction from "normal" to "alternate"');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 0, 1 ] },
-                         { iterations: 2,
-                           duration: 10000,
-                           direction: 'normal' });
-
-  anim.currentTime = 17000;
-  anim.effect.timing.direction = 'alternate-reverse';
-
-  assert_equals(getComputedStyle(div).opacity, '0.7',
-                'change direction from "normal" to "alternate-reverse"');
-}, 'change direction from "normal" to "alternate-reverse"');
-
-test(function(t) {
-  var div = createDiv(t);
-  var anim = div.animate({ opacity: [ 0, 1 ] },
-                         { fill: 'backwards',
-                           duration: 10000,
-                           direction: 'normal' });
-
-  // test for a flip of value at the currentTime = 0
-  anim.effect.timing.direction = 'reverse';
-
-  assert_equals(getComputedStyle(div).opacity, '1',
-                'change direction from "normal" to "reverse" ' +
-                'at the starting point');
-}, 'change direction from "normal" to "reverse" when currentTime is 0');
-
-</script>
-</body>

--- a/testing/web-platform/tests/web-animations/interfaces/AnimationEffectTiming/iterations.html
+++ b/testing/web-platform/tests/web-animations/interfaces/AnimationEffectTiming/iterations.html
@@ -52,10 +52,43 @@ test(function(t) {
 test(function(t) {
   var div = createDiv(t);
   var anim = div.animate({ opacity: [ 0, 1 ] }, 2000);
   assert_throws({ name: 'TypeError' }, function() {
     anim.effect.timing.iterations = NaN;
   });
 }, 'Throws when setting a NaN value');
 
+test(function(t) {
+  var div = createDiv(t);
+  var anim = div.animate(null, { duration: 100000, fill: 'both' });
+
+  anim.finish();
+
+  assert_equals(anim.effect.getComputedTiming().progress, 1,
+                'progress when animation is finished');
+  assert_equals(anim.effect.getComputedTiming().currentIteration, 0,
+                'current iteration when animation is finished');
+
+  anim.effect.timing.iterations = 2;
+
+  assert_times_equal(anim.effect.getComputedTiming().progress, 0,
+                     'progress after adding an iteration');
+  assert_times_equal(anim.effect.getComputedTiming().currentIteration, 1,
+                     'current iteration after adding an iteration');
+
+  anim.effect.timing.iterations = 0;
+
+  assert_equals(anim.effect.getComputedTiming().progress, 0,
+                'progress after setting iterations to zero');
+  assert_equals(anim.effect.getComputedTiming().currentIteration, 0,
+                'current iteration after setting iterations to zero');
+
+  anim.effect.timing.iterations = Infinity;
+
+  assert_equals(anim.effect.getComputedTiming().progress, 0,
+                'progress after setting iterations to Infinity');
+  assert_equals(anim.effect.getComputedTiming().currentIteration, 1,
+                'current iteration after setting iterations to Infinity');
+}, 'Can be updated while the animation is in progress');
+
 </script>
 </body>