title: How to pass a variables for refetchQueries in Apollo
body: <p>I am not sure what the best practice is to pass <code>variables</code> in <code>refetchQueries</code> options. In below example the variables is <code>{id: this.props.item.id}</code></p>
  
  <p>But passing <code>this.props.item.id</code> returned an <strong>error</strong> since <code>MyComponent</code> is not yet instantiated hence <code>this.props</code> is undefined.</p>
  
  <pre><code>function mapStateToProps(state) {
    return {
      item: state.item
    };
  }
  
  MyComponent = connect(mapStateToProps, matchDispatchToProps)(
    MyComponent
  );
  
  MyComponent = graphql(createItemImage, {
    name: "createItemImage",
    options: {
      refetchQueries: [
        {
          query: getEntity,
          variables: { id: this.props.item.id }
        }
      ]
    }
    })(MyComponent);
  </code></pre>
  
  <p>The <code>id</code> value will only be available during runtime.</p>
  
  <p>Thanks in advance!</p>