title: React-Virtualized Autosizer calculates height as 0 for VirtualScroll
body: <p>Where AutoSizer's width gives me an appropriate value, I'm consistently getting an Autosizer height of 0, which causes the VirtualScroll component not to display. However, if i use the disableHeight prop and provide VirtualScroll with a fixed value for height (i.e. 200px), VirtualScroll displays rows as expected. Can anyone see whats wrong?</p>
  
  <p>Ultimately, the Autosizer is meant to live inside a Material-ui Dialog component, but I have also tried simply rendering the autosizer into a div. Same issue.</p>
  
  <pre><code>render() {
  return (
    &lt;Dialog
      modal={false}
      open={this.state.open}
      onRequestClose={this.handleClose}
      contentStyle={pageOptionsDialog.body}
    &gt;
    &lt;div&gt;
      &lt;AutoSizer&gt;
        {({ width, height }) =&gt; (
          &lt;VirtualScroll
            id="virtualScroll"
            onRowsRendered={this.props.loadNextPage}
            rowRenderer={this.rowRenderer}
            height={height}
            rowCount={this.props.rowCount}
            rowHeight={30}
            width={width}
          /&gt;
        )}
      &lt;/AutoSizer&gt;
    &lt;/div&gt;
  &lt;/dialog&gt;
  )}
  </code></pre>