Display errors thrown from beforeAll/afterAll

Other changes along the way: 

* More fully disable the unused symbolSummary to avoid creating unused DOM nodes.
* Add a stack property to `DeveloperError`/`RuntimeError` so that they display correctly when thrown from specs.
* Fix a number of specs and bugs that were hidden before:
   * `imageryLayer_reproject` context cache object `destroy()` method was broken.
   * `SunPostProcess.destroy()` was broken.
   * `HomeButton` specs destroyed objects in the wrong order.