Improving a11y of BottomBar and ControlBar

[myasonik]

Summary

Closes #2855

Wasn't sure what the solution was going to look like so I played with it a bit and this is what I ended up with. Juggling a few things right now though so I'm hoping someone from the EUI team can help me push this PR over the finish line - all the jest tests seem to be broken for some reason?

Help!

Edit: something was wonked in my environment. Updating the snapshots now worked as expected.

Checklist

- [ ] Check against all themes for compatibility in both light and dark modes

• Checked in mobile
• Checked in IE11 and Firefox
• Props have proper autodocs
• Added documentation examples
• Added or updated jest tests
  - [ ] Checked for breaking changes and labeled appropriately
• Checked for accessibility including keyboard-only and screenreader modes
• A changelog entry exists and is marked appropriately

[myasonik]

jenkins test this

[cchaos]

Thanks for tackling this one. I just did a quick code review first.

[myasonik]

@thompsongl @chandlerprall Could y'all take a look at my tests and tell me what I'm doing wrong?

For some reason the jest tests now return a bunch of loading states though I don't see what I may have done to cause that in the PR...

[thompsongl]

For some reason the jest tests now return a bunch of loading states though I don't see what I may have done to cause that in the PR...

Context menu tests with icons have been flaky for a bit: #2765

Were you consistently getting failures before updating the snapshot?

[JoshMock]

jenkins retest this please

[myasonik]

I'm pretty consistently getting the same results locally:

• Running yarn test-unit -u will give me the expected mock
• Whatever is run when I try to commit will give the still loading mock

That doesn't happen 100% of the time but pretty consistently now...

[thompsongl]

@myasonik Go ahead and revert changes to any snapshots you deem unrelated to bottombar and controlbar. Use the -n flag if necessary to push and we'll see what CI does.

I'm working on mocking EuiIcon to prevent this kind of thing in the future.

[thompsongl]

@myasonik Rebase or merge master and any snapshot flakiness should be resolved

[cchaos]

Thanks for the explanations!

[kibanamachine]

Preview documentation changes for this PR: https://eui.elastic.co/pr_2861/