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?
case 'font-face-src':
    case 'font-face-uri':
    case 'font-face-format':
    case 'font-face-name':
    case 'missing-glyph': {
      return pushStartGenericElement(target, props, type, responseState);
    }
    case 'html': {
      if (formatContext.insertionMode === ROOT_HTML_MODE) {
        
        
        
        target.push(DOCTYPE);
      }
      return pushStartGenericElement(target, props, type, responseState);
    }
    default: {
      if (type.indexOf('-') === -1 && typeof props.is !== 'string') {
        
        return pushStartGenericElement(target, props, type, responseState);
      } else {
        
        return pushStartCustomElement(target, props, type, responseState);
      }
    }
  }
}
const endTag1 = stringToPrecomputedChunk('</');
const endTag2 = stringToPrecomputedChunk('>');
export function pushEndInstance(