Remove shouldComponentUpdate from MarkdownVisComponent, as it is causing (#21501) (#21583)

src/core_plugins/markdown_vis/public/markdown_vis_controller.js

@@ -6,29 +6,6 @@ import { Markdown } from 'ui/markdown/markdown';
  */
 class MarkdownVisComponent extends Component {
 
-  /**
-   * This method will be called when props or the state has been updated, and
-   * we should return whether we want the render method to be called again (true)
-   * or if we know that the render method wouldn't produce anything different and
-   * we don't need it to be called (false).
-   *
-   * We only need to render if one of the parameters used in the render function
-   * actually changed. So we prevent calling render if none of it changed.
-   */
-  shouldComponentUpdate(props) {
-    const shouldUpdate = props.fontSize !== this.props.fontSize ||
-        props.openLinksInNewTab !== this.props.openLinksInNewTab ||
-        props.markdown !== this.props.markdown;
-
-    // If we won't update, we need to trigger the renderComplete method here,
-    // since we will never render and thus never get to componentDidUpdate.
-    if (!shouldUpdate) {
-      this.props.renderComplete();
-    }
-
-    return shouldUpdate;
-  }
-
   /**
    * Will be called after the first render when the component is present in the DOM.
    *