function getElementStyle(element) {
  assertHTMLElement(element);
  return genericPropertyGet(
      Methods.STYLE_GETTER, element, 'style', function(style) {
        return style instanceof CSSStyleDeclaration;
      });
}
Returns an element's style without falling prey to things like
<form><input name="style"></form>.
@param {!Element} element
@return {!CSSStyleDeclaration}