Featurebug/combobox input focus

[chandlerprall]

Summary

fixes #1195 fixes #1251 closes #589

• escape key now closes an open combo box
• keeps browser focus on the combo box's input instead of shifting focus to the popover options
• aria roles for screen reading
• compressed prop added to EuiComboBox ( @cchaos please verify & review this )
• hides the dropdown icon if noSuggestions is present

Checklist

• This was checked in mobile
• This was checked in IE11
• [ ] This was checked in dark mode
• Any props added have proper autodocs
• Documentation examples were added
• A changelog entry exists and is marked appropriately
• This was checked for breaking changes and labeled appropriately
• Jest tests were updated or added to match the most common scenarios
• This was checked against keyboard-only and screenreader scenarios

[cchaos]

@chandlerprall , I'm not sure if you saw but I pushed a PR against your branch with some more fixes: chandlerprall#2

[snide]

The ownFocus popovers can sometimes cause problems with the esc from a combo box. You end up in a loop. I don't know a good solution for this one.

[cjcenizal]

This looks great overall! I had a few comments but I also think the UX of using ESC to open and close the options list to be slightly improved. I think the existing UX is confusing because ESC causes your focus to vanish from the user's perspective. What do you think of mimicking the UX of react-select whereby ESC closes the options list but retains focus on the input? The user can reopen the input by hitting an arrow key or enter. This way as a user I'd feel more in control of where the focus is.

[chandlerprall]

@snide what do you think about CJ's Escape key comment (copied relevant portion here)?

I think the existing UX is confusing because ESC causes your focus to vanish from the user's perspective. What do you think of mimicking the UX of react-select whereby ESC closes the options list but retains focus on the input?

That would resolve the popover esc->popup->esc->popup loop. I went back and forth on if Escape should remove focus or not, and am not opinionated either way.

[snide]

@chandlerprall Sounds good to me. Good idea @cjcenizal

[chandlerprall]

@cjcenizal everything should be addressed

[cjcenizal]

Tested in browser, UX of Escape key is great! Thanks for the changelog updates, too. Nice work!