message: packages/dev-utils: added addRootChild to DevAppBuilder
diff: */
  import { hot } from 'react-hot-loader/root';
  -import React, { FC, ComponentType } from 'react';
  +import React, { FC, ComponentType, ReactNode } from 'react';
  import ReactDOM from 'react-dom';
  import { BrowserRouter } from 'react-router-dom';
  import BookmarkIcon from '@material-ui/icons/Bookmark';
  @@ -43,6 +43,7 @@ type BackstagePlugin = ReturnType<typeof createPlugin>;
  class DevAppBuilder {
  private readonly plugins = new Array<BackstagePlugin>();
  private readonly factories = new Array<ApiFactory<any, any, any>>();
  + private readonly rootChildren = new Array<ReactNode>();
  /**
  * Register one or more plugins to render in the dev app
  @@ -62,6 +63,16 @@ class DevAppBuilder {
  return this;
  }
  + /**
  + * Adds a React node to place just inside the App Provider.
  + *
  + * Useful for adding more global components like the AlertDisplay.
  + */
  + addRootChild(node: ReactNode): DevAppBuilder {
  + this.rootChildren.push(node);
  + return this;
  + }
  +
  /**
  * Build a DevApp component using the resources registered so far
  */
  @@ -79,6 +90,7 @@ class DevAppBuilder {
  return (
  <AppProvider>
  <AlertDisplay />
  + {this.rootChildren}
  <BrowserRouter>
  <SidebarPage>
  {sidebar}
  