Part of ENG-4319.
Before deletion, the user is warned about possible contained chats. For subchannel deletion, the modal looks like this:
iOS:
{F648099}
Andriod:
{F648100}
When deleting a whole community, message changes:
iOS:
{F648101}
Android:
{F648102}
When there are no contained chats, the confirmation modal does not pop up.
Depends on D8526.