message: refactor(animations): do not assign to innerHTML
  This should not change behavior, but it prevents false-positive warnings in various static analysis
  tools, including tools used internally at Google.
  PR Close
diff: @@ -72,7 +72,7 @@ export class CssKeyframesDriver implements AnimationDriver {
  keyframeStr += `}\n`;
  const kfElm = document.createElement('style');
  - kfElm.innerHTML = keyframeStr;
  + kfElm.textContent = keyframeStr;
  return kfElm;
  }
  