title: how is it possible to use flowtype to define a prop in react context of a component?
body: <p>When using <a href="http://flowtype.org" rel="noreferrer">flowtype</a> to define a prop in the <a href="https://facebook.github.io/react/docs/context.html" rel="noreferrer">context</a> in this way</p>
  
  <pre><code>// @flow
  type MyType = Object;
  class CustomView extends React.Component {
      static childContextTypes = {
          someProp: MyType
      }
      getChildContext() {
          return {
              someProp: this.props.someProp
          };
      }
  }
  </code></pre>
  
  <p>I got the following error:</p>
  
  <blockquote>
    <p>CustomView: type specification of child context <code>someProps</code> is
    invalid; the type checker function must return <code>null</code> or an <code>Error</code>
    but returned a object. You may have forgotten to pass an argument to
    the type checker creator (arrayOf, instanceOf, objectOf, oneOf,
    oneOfType, and shape all require an argument).</p>
  </blockquote>
  
  <p>So I am forced to use <code>propTypes.object</code> instead of <code>Object</code>.</p>