Cannot navigate after clicking the group expand/collapse icon

[mbechev]

Description

Cannot navigate through cells using arrow keys after clicking the expand/collapse icon. The group header is no longer focused which disrupts. the built-in navigation.

Steps To Reproduce

Click the icon and try to navigate with the arrow keys:

https://stackblitz.com/edit/angular-jckvdf?file=src%2Fapp%2Fapp.component.ts

Actual Behavior

Cannot navigate to other cells after using the group expand/collapse icon.

The user can use the arrow keys as usual, if clicking the group header text.

Expected Behavior

The user should be able to navigate through cells regardless if the header text or group expand/collapse icon is used.

[DanielTakev]

Subscribed for tracking