Marking as P3 since this isn't affecting a prod use case, but it's making it very difficult to diagnose some problems using the Ozone / sandbox.

* Run Chrome OS in "simple chrome"'s Ozone/sandbox mode. Use the --ash-debug-shortcuts flag.
* Enter tablet mode (Ctrl-Alt-Shift-T)
* Click on the app list button
* Click on the app list button once more
* Observe the crash

Looking into it a tiny bit, is seems like the "this" object is nullptr in this method:

    void AppListView::Back()

And that causes the crash. I can add:

  if (!this)
    return;

At the start of that method, which prevents the crash, but then the button does nothing after the first click. I'm not even sure what it's supposed to do in this situation.