chromium/third_party/blink/web_tests/svg/animations/mozilla/animateMotion-mpath-pathLength-1.svg

<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" onload="loaded()">
  <defs>
    <path id="path" pathLength="100" d="M-200,0 h400" />
  </defs>
  <rect width="100%" height="100%" fill="lime"/>

  <!-- calcMode="linear" -->
  <rect x="10" y="10" width="100" height="100" fill="red"/>
  <rect x="10" y="10" width="100" height="100" fill="lime">
    <animateMotion dur="1s" keyPoints="0;1" keyTimes="0;1" calcMode="linear">
      <mpath xlink:href="#path" />
    </animateMotion>
  </rect>

  <!-- calcMode="paced" -->
  <rect x="10" y="110" width="100" height="100" fill="red"/>
  <rect x="10" y="110" width="100" height="100" fill="lime">
    <animateMotion dur="1s">
      <mpath xlink:href="#path" />
    </animateMotion>
  </rect>

<script>
if (window.testRunner)
    testRunner.waitUntilDone();

function loaded() {
    document.documentElement.setCurrentTime(0.5);
    document.documentElement.pauseAnimations();

    if (window.testRunner)
        testRunner.notifyDone();
}
</script>
</svg>