message: View header fixes. Show left|right|icon|title only if appropriate are passed
diff: @@ -428,29 +428,39 @@ export default class View extends Component {
  style={this.calcHeaderSwipeStyles(panel.props.id).item}
  key={panel.key || panel.props.id || `panel-header-${i}`}
  >
  + { (panel.props.header.left || panel.props.header.icon) &&
  <div className="View__header-left">
  + { panel.props.header.icon &&
  <div
  className="View__header-icon"
  style={this.calcHeaderSwipeStyles(panel.props.id).leftIcon}
  >
  {panel.props.header.icon}
  </div>
  + }
  + { panel.props.header.left &&
  <div
  className="View__header-left-in"
  style={this.calcHeaderSwipeStyles(panel.props.id).leftIn}
  >
  {panel.props.header.left}
  </div>
  + }
  </div>
  + }
  + { panel.props.header.title &&
  <div
  className="View__header-title"
  style={this.calcHeaderSwipeStyles(panel.props.id).title}
  >
  {panel.props.header.title}
  </div>
  + }
  + { panel.props.header.right &&
  <div className="View__header-right">
  {panel.props.header.right}
  </div>
  + }
  </div>
  ))}
  </div>
  