[TS] Allow basic/incomplete extension of ChoiceSetInput

[dclaux]

Related Issue

Fixes #5091

NOTE: This PR fixes the issue as reported: a custom input that extends ChoiceSetInput and only overrides its internalRender method will no longer cause the host app to break. However, the custom input will still have to override additional methods in order to participate in the input validation mechanism and to meet accessibility requirements.

Description

• ChoiceSetInput.updateInputControlAriaLabelledBy will not throw anymore on custom inputs that extend ChoiceSetInput and only override internalRender.
• Non-issue related: ChoiceSetInput.internalApplyAriaCurrent should not be marked as protected because it shouldn't be overridable. This PR makes it private.

How Verified

Verified manually in adaptivecards-designer-app

Microsoft Reviewers: Open in CodeFlow

[ghost]

Hi @dclaux. Thanks for helping make the AdaptiveCards JS renderer + tooling better. As additional verification, once the JS build succeeds, please go to the test site to test out your website/designer changes.

[ghost]

Hi @dclaux. This non-spec pull request has had no recent activity for the past 5 days . Please take the necessary actions (review, address feedback or commit if reviewed already) to move this along.

[ghost]

Hi @dclaux; Thanks for taking action on your previously stale pull request. Resetting staleness.