Redirect widgets to another location before deleting them
Redirect widgets to another location before deleting them

This is so that shutdown hooks in the widget can correctly fire, such as Jitsi's hook to abandon its hold on the webcam.

Fixes https://github.com/vector-im/riot-web/issues/7351
matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk