[Accessibility] Saved Object Finder traps focus

[cjcenizal]

If you go into a dashboard, open the "Add Panels" menu, and then try to alt-tab backwards out of the "Visualizations filter" input, you end up tabbing to the first visualization in the list.

The desired behavior is to tab back to the "Close menu" caret icon in the top right corner.

This undesirable behavior is caused by this event handler on line 14 of saved_object_finder.html:

ng-keydown="finder.filterKeyDown($event)"

For some reason, this handler (line 135 of saved_object_finder.js) is capturing the tab event. Upon further digging, it looks like there's a lot of logic in here for keyboard accessibility (e.g. the hitKeyDown method on line 160). We should look into this and ask the author for background on this functionality. If the default tabbing behavior is sufficient for users to navigate this component, then we can remove this functionality and just give individual elements on the screen basic keyboard-accessibility.

[stacey-gammon]

That code is 2 - 3 years old and so difficult to point to any single author. It looks like everything works properly when it's just ripped out so that's what I'm inclined to do...