List: expose NoDataText to screen readers when empty (T1329047)

[dmlvr]

No description provided.

[Copilot]

Pull request overview

This PR addresses an accessibility gap in dxList where the empty-state message (noDataText) was not being exposed to screen readers via an aria-label on the scroll view content (focus target). It updates the List’s internal empty-message rendering to synchronize aria-label with the empty state and adjusts/extends widget test coverage accordingly.

Changes:

• Update ListBase to set/clear the focus target’s aria-label based on whether the list is in the empty state, using the empty message text.
• Export the dx-empty-collection CSS class constant from collection_widget.base.ts for reuse in ListBase.
• Add/update accessibility tests for List, SelectBox, and Lookup to validate the new aria-label behavior on empty lists.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
packages/devextreme/testing/tests/DevExpress.ui.widgets/listParts/commonTests.js	Adds coverage ensuring scrollview content gets aria-label=noDataText in empty-state scenarios (init, runtime changes, clearing).
packages/devextreme/testing/tests/DevExpress.ui.widgets.editors/selectBox.tests.js	Updates ARIA assertions to expect the list’s empty-state aria-label on the scrollview content.
packages/devextreme/testing/tests/DevExpress.ui.widgets.editors/lookup.tests.js	Updates ARIA assertions to expect the list’s empty-state aria-label and verifies it toggles with data presence.
packages/devextreme/js/__internal/ui/list/list.base.ts	Implements empty-state aria-label synchronization on the list focus target (scrollview content).
packages/devextreme/js/__internal/ui/collection/collection_widget.base.ts	Exports EMPTY_COLLECTION constant so List can reliably detect empty state via the shared class name.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated no new comments.