old_contents: /** @jsx REACT.DOM */
  import React from 'react';
  
  export default React.createClass({
    render: function () {
      return (
        <div className="control-panel">
          <p>{this.props.track ? this.props.track.title : 'CONTROL PANEL'}</p>
        </div>
      );
    }
  });
  
new_contents: /** @jsx REACT.DOM */
  import React from 'react';
  
  export default React.createClass({
    render: function () {
  
      const trackTitle = this.props.track ? this.props.track.title : 'CONTROL PANEL';
  
      return (
        <div className="control-panel">
          <p>{trackTitle}</p>
        </div>
      );
  
    }
  });
  
subject: Move control panel title into a variable