When you do `<Foo />` but Foo is not a valid string or function, we show an error message:

https://github.com/facebook/react/blob/92c84a6f37245f4fbe3ce5dc50845856201637fa/src/isomorphic/classic/element/ReactElementValidator.js#L196

We include the owner name ("Please check the render method of Bar.") but not the full parent stack which we show for some of our other warnings like key warnings and prop types. We should call into ReactComponentTreeHook to get the full stack if possible. 

ComponentClass = React.createClass({
      render: function() {
        return React.createElement('div');
      },
    });
  });
  it('warns for keys for arrays of elements in rest args', () => {
    spyOn(console, 'error');
    var Component = React.createFactory(ComponentClass);
    Component(null, [Component(), Component()]);
    expectDev(console.error.calls.count()).toBe(1);
    expectDev(console.error.calls.argsFor(0)[0]).toContain(
      'Each child in an array or iterator should have a unique "key" prop.'
    );
  });
  it('warns for keys for arrays of elements with owner info', () => {
    spyOn(console, 'error');
    var Component = React.createFactory(ComponentClass);
    var InnerClass = React.createClass({
      displayName: 'InnerClass',
      render: function() {
        return Component(null, this.props.childSet);
      },
    });
    var InnerComponent = React.createFactory(InnerClass);
    var ComponentWrapper = React.createClass({
      displayName: 'ComponentWrapper',
      render: function() {
        return InnerComponent({childSet: [Component(), Component()] });
      },