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?
defaultValue = propValue;
          break;
        case 'checked':
          checked = propValue;
          break;
        case 'value':
          value = propValue;
          break;
        default:
          pushAttribute(target, responseState, propKey, propValue);
          break;
      }
    }
  }
  if (checked !== null) {
    pushAttribute(target, responseState, 'checked', checked);
  } else if (defaultChecked !== null) {
    pushAttribute(target, responseState, 'checked', defaultChecked);
  }
  if (value !== null) {
    pushAttribute(target, responseState, 'value', value);
  } else if (defaultValue !== null) {
    pushAttribute(target, responseState, 'value', defaultValue);
  }
  target.push(endOfStartTagSelfClosing);
  return null;
}
function pushStartTextArea(
  target: Array<Chunk | PrecomputedChunk>,
  props: Object,