Animations: Make perf tests for web animations animate properly.

PerformanceTests/Animation/api-set-current-time-balls-keyframe-animations.html

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 Copyright (c) 2012 Cameron Adams. All rights reserved.
 Copyright (c) 2012 Code Aurora Forum. All rights reserved.
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@@ skipping 114 matching lines @@
             y += dy * dt;
         } else {
             t += collision.dt;
             x = collision.x;
             y = collision.y;
             dx = collision.dx;
             dy = collision.dy;
         }
         allParticleKeyframes[index].push(generateKeyframe(t, x, y));
     }
-
-    return keyframes;
 }
 
 function generateKeyframe(t, x, y) {
     return {left: x + "px", top: y + "px", offset: t / animationDuration };
 }
 
 function Particle(index)
 {
     // Create visual element for the particle.
     var domNode = document.createElement('span');
     document.body.appendChild(domNode);
 
     // Set colour of element.
     domNode.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
 
     function start() {
-        var player = domNode.animate(allParticleKeyframes[index], {easing: "linear", iterations: Infinity, direction: "alternate", duration: animationDuration});
+        var player = domNode.animate(allParticleKeyframes[index], {easing: "linear", iterations: Infinity, direction: "alternate", duration: animationDuration * 1000});
         player.pause();
         this.player = player;
     }
 
     function destroy()
     {
         document.body.removeChild(domNode);
     }
 
     this.start = start;
     this.destroy = destroy;
 }
 
 var start = null;
 
 function advance(timestamp)
 {
     if (start == null)
         start = timestamp;
     for (var x in particles) {
-        particles[x].player.currentTime = (timestamp - start) / 1000;
+        particles[x].player.currentTime = timestamp - start;
     }
     if (particles.length !== 0)
         requestAnimationFrame(advance);
 }
 
 requestAnimationFrame(advance);
 
 function onCompletedRun() {
     testRunning = false;
     stopTrackingFrameRate();
 
     for (var i = 0; i < particles.length; i++)
         particles[i].destroy();
     particles = [];
 }
 </script>
 <style id="keyframes"></style>
 </head>
 </html>