Web Animations: Migrate SVG path interpolation to interpolation types

third_party/WebKit/LayoutTests/animations/svg-attribute-interpolation/resources/interpolation-test.js

 /* Copyright 2015 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  * Exported function:
  *  - assertAttributeInterpolation({property, from, to, [fromComposite], [toComposite], [underlying]}, [{at: fraction, is: value}])
  *        Constructs a test case for each fraction that asserts the expected value
  *        equals the value produced by interpolation between from and to composited
  *        onto underlying by fromComposite and toComposite respectively using
  *        SMIL and Web Animations.
@@ skipping 40 matching lines @@
           return (parseFloat(n).toFixed(2)).
               replace(/\.\d+/, function(m) {
                 return m.replace(/0+$/, '');
               }).
               replace(/\.$/, '').
               replace(/^-0$/, '0');
         });
   }
 
   function normalizeValue(value) {
+    if (value === null) {
+      return '-NULL-';
+    }
     return roundNumbers(value).
         // Place whitespace between tokens.
         replace(/([\w\d.]+|[^\s])/g, '$1 ').
         replace(/\s+/g, ' ');
   }
 
   function createTarget(container) {
     var targetContainer = createElement('div');
     var template = document.querySelector('#target-template');
     if (template) {
@@ skipping 236 matching lines @@
           target.container.setCurrentTime(expectation.at);
         } else {
           console.warn(`Unable to test SMIL from ${params.from} to ${params.to}`);
           target.container.remove();
           target.measure = function() {};
         }
         break;
       case 'Web Animations':
         // Replace 'transform' with 'svgTransform', etc. This avoids collisions with CSS properties or the Web Animations API (offset).
         var prefixedProperty = 'svg' + params.property[0].toUpperCase() + params.property.slice(1);
-        target.animate([
-          {
+        var keyFrames = [];
+        if (params.from !== '') {
+          keyFrames.push({
+            offset: 0,
             [prefixedProperty]: params.from,
             composite: params.fromComposite,
-          },
-          {
+          })
+        }
+        if (params.to !== '') {
+          keyFrames.push({
+            offset: 1,
             [prefixedProperty]: params.to,
             composite: params.toComposite,
-          },
-        ], {
+          })
+        }
+        target.animate(keyFrames, {
           fill: 'forwards',
           duration: 1,
           easing: createEasing(expectation.at),
           delay: -0.5,
           iterations: 0.5,
         });
         break;
       default:
         console.error('Unknown test method: ' + method);
       }
@@ skipping 72 matching lines @@
     return loadScript('../../resources/testharnessreport.js');
   }).then(() => {
     var asyncHandle = async_test('This test uses interpolation-test.js.')
     requestAnimationFrame(() => {
       runTests().then(() => asyncHandle.done());
     });
   });
 
   window.assertAttributeInterpolation = assertAttributeInterpolation;
 })();