bug(many): duplicate code for exposing overlays for modals

[zarend]

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

We have duplicated code for logic for exposing overlays to modals. some browsers won't expose the accessibility node of the overlay if there is an aria-modal and the live element is outside of it. This method works around the issue by pointing the aria-owns of all modals to the live element.

Action item to consider de-duplicating this with the LiveAnnouncer and any other occurrences.

Note that the selector here is limited to CDK overlays at the moment in order to reduce the section of the DOM we need to look through. This should cover all the cases we support, but the selector can be expanded if it turns out to be too narrow.

Reproduction

Search codebase for TODOS references this issue report.

git grep 'TODO(http://github.com/angular/components/issues/26853)'; git grep '#26853';

Expected Behavior

no occurrences

Actual Behavior

multiple occurrences

Environment

N/A