Test transform-style: preserve-3d support

test-preserve-3d.js

function testPreserve3DSupport() {
  const element = document.createElement('p');
  document.body.insertBefore(element, null);
  const propName = 'transform-style';
  element.style[propName] = 'preserve-3d';
  const propValue = window.getComputedStyle(element, null).getPropertyValue(propName);
  document.body.removeChild(element);
  return (propValue === 'preserve-3d');
}