When setting boolean attributes on Web Components
`<x-search somebool name={this.props.name} />`
they get rendered as attribute/value pairs instead
`<x-search somebool="true" name={this.props.name}>`

This causes problems with some AMP components, for eg. `<amp-iframe />` which has a `resizable` attribute that gets rendered as `resizable="true"`. This results in non valid AMP content and developers crying with blood tears on their keyboards :)
> The attribute 'resizable' in tag 'amp-iframe' is set to the invalid value 'true'. (see https://www.ampproject.org/docs/reference/components/amp-iframe)

Is there any reason for the current behaviour? Will changing this break something else?
STRING,
    false, 
    attributeName.toLowerCase(), 
    null, 
    false, 
    false, 
  );
});
const xlinkHref = 'xlinkHref';
properties[xlinkHref] = new PropertyInfoRecord(
  'xlinkHref',
  STRING,
  false, 
  'xlink:href',
  'http://www.w3.org/1999/xlink',
  true, 
  false, 
);
['src', 'href', 'action', 'formAction'].forEach(attributeName => {
  properties[attributeName] = new PropertyInfoRecord(
    attributeName,
    STRING,
    false, 
    attributeName.toLowerCase(), 
    null, 
    true, 
    true, 
  );
});