message: update testhost to support props
diff: @@ -47,8 +47,8 @@ class TestRootComponent extends PrimedComponent {
  }
  // tslint:disable-next-line: no-unnecessary-override
  - public async createAndAttachComponent<T>(id: string, type: string): Promise<T> {
  - return super.createAndAttachComponent<T>(id, type);
  + public async createAndAttachComponent<T>(id: string, type: string, props?: any): Promise<T> {
  + return super.createAndAttachComponent<T>(id, type, props);
  }
  // tslint:disable-next-line: no-unnecessary-override
  @@ -206,10 +206,10 @@ export class TestHost {
  public async createAndAttachComponent<T extends IComponentLoadable>(
  id: string,
  type: string,
  - services?: [string, Promise<any>][],
  + props?: any,
  ): Promise<T> {
  const root = await this.root;
  - return root.createAndAttachComponent<T>(id, type);
  + return root.createAndAttachComponent<T>(id, type, props);
  }
  /**
  