Terra-core: [Radio, Checkbox, Time Input]: Document the need to mock window.matchMedia for jest tests

[PseudoFaux]

Issue Description

After consuming terra-form-radio and terra-form-checkbox, our jest tests started to fail with this error:

TypeError: window.matchMedia is not a function
      at Object.isConsideredMobileDevice (node_modules/terra-form-radio/lib/_RadioUtil.js:8:17)
      at Radio (node_modules/terra-form-radio/lib/Radio.js:140:131)

The file is here: _RadioUtil.js.

The same issue exists with CheckboxUtil as well.

Issue Type

• [ ] New Feature
• [ ] Enhancement
• [X] Bug
• [X] Other

Expected Behavior

Our jest tests should not fail when consuming terra-form-radio/terra-form-checkbox

Steps to Reproduce

1. Consume radio/checkbox
2. Run jest test on a component that uses radio/checkbox

Environment

• Component Version: terra-form-radio (2.0.0), terra-form-checkbox (2.0.0)
• Browser Name and Version: All
• Operating System and version (desktop or mobile): All

[PseudoFaux]

After a slight bit of investigation and discussion with @yuderekyu, we have found that there is a way to get around the issue by mocking out window.matchMedia like so:

window.matchMedia = () => ({ matches: true });

like you have in your jestsetup.js file.

Is this something that we, as a consumer, should be doing on our end?

[bjankord]

Yes, we'd recommend updating your jestsetup.js file to mock window.matchMedia with the code @yuderekyu provided.

[PseudoFaux]

Is it possible to add that recommendation to the documentation of those components? It would surely be helpful for other consumers to know that you _must_ mock window.matchMedia for jest tests not to fail.

[bjankord]

@PseudoFaux Would you be up for sending a PR to update the doc?

[prachigotkhindikar1]

@PseudoFaux / @bjankord, checking to see if a PR has already been made to update the doc. If not, I would be happy to make one. Thanks!

[bjankord]

@prachigotkhindikar1 Feel free to send over a PR!

[prachigotkhindikar1]

@bjankord, Please review https://github.com/cerner/terra-core/pull/2532

[bjankord]

Looks good, just need to update the changelog files.