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diff --git a/catapult/third_party/polymer/components/web-animations-js/src/web-animations-bonus-object-form-keyframes.js b/catapult/third_party/polymer/components/web-animations-js/src/web-animations-bonus-object-form-keyframes.js
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+++ b/catapult/third_party/polymer/components/web-animations-js/src/web-animations-bonus-object-form-keyframes.js
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+// Copyright 2016 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+//     You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//     See the License for the specific language governing permissions and
+// limitations under the License.
+
+(function(shared) {
+  // If the polyfill is being loaded in a context where Element.animate is
+  // supported but object-form syntax is not, then creating an animation
+  // using the new syntax will either have no effect or will throw an exception.
+  // In either case, we want to proceed to load this part of the polyfill.
+  //
+  // The test animation uses an opacity other than the one the element already
+  // has, and doesn't need to change during the animation for the test to work.
+  // After the test, the element's opacity will be left how we found it:
+  // - If the animation is not created, the test will leave the element's
+  //   opacity untouched at originalOpacity.
+  // - If the animation is created, it will be cancelled, and leave the
+  //   element's opacity at originalOpacity.
+  // - If the animation is somehow created and runs without being cancelled,
+  //   when it finishes after 1ms, it will cease to have any effect (because
+  //   fill is not specified), and opacity will again be left at originalOpacity.
+  var element = document.documentElement;
+  var animation = null;
+  var animated = false;
+  try {
+    var originalOpacity = getComputedStyle(element).getPropertyValue('opacity');
+    var testOpacity = originalOpacity == '0' ? '1' : '0';
+    animation = element.animate({'opacity': [testOpacity, testOpacity]},
+        {duration: 1});
+    animation.currentTime = 0;
+    animated = getComputedStyle(element).getPropertyValue('opacity') == testOpacity;
+  } catch (error) {
+  } finally {
+    if (animation)
+      animation.cancel();
+  }
+  if (animated) {
+    return;
+  }
+
+  var originalElementAnimate = window.Element.prototype.animate;
+  window.Element.prototype.animate = function(effectInput, options) {
+    if (window.Symbol && Symbol.iterator && Array.prototype.from && effectInput[Symbol.iterator]) {
+      // Handle custom iterables in most browsers by converting to an array
+      effectInput = Array.from(effectInput);
+    }
+
+    if (!Array.isArray(effectInput) && effectInput !== null) {
+      effectInput = shared.convertToArrayForm(effectInput);
+    }
+
+    return originalElementAnimate.call(this, effectInput, options);
+  };
+})(webAnimationsShared);