add keyboard navigation over disabled days

[ovidiu1]

Feature Details:

• Disabled days are now navigable via keyboard.

• Display tooltip on focus (only on disable days)

• Set "Unavailable" on the accessible name (only on disable days)

Tested:

• Chrome
• IE 11
  

[ovidiu1]

I will do an update on this. (after #499)

[jorenbroekema]

Hi Ovidiu,

We had a meeting as a team discussing the accessibility concerns with this keyboard navigation over disabled, and came to an agreement on the approach:

• Instead of using <button>, use <div> with role=“button“
• Use disabled attribute for styling this div
• Use aria-disabled for screen readers (I don't think the unavailable tooltip is necessary then)
• Manage click/enter/space events manually (adding listeners)

It's up to you whether you want to continue on this branch / PR or if you want to start a new one. If you do start a new one I think it would be wise to maybe start with tests first that align with the approach I mentioned above, get the okay, and then implement and fix failing tests.

[claassistantio]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ ovidiu1
❌ Ovidiu

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[ovidiu1]

I will close this PR and i will start a new one.