If you've left a group, we shouldn't show it in any pickers except the
blocking manager (`AddToBlockListViewController`). Before this commit,
we were showing it in a few places. That might let you sorta-send a
message to a group you'd left.
I enumerated all the places where we have pickers, and what their
behavior should be.
| Description | Code | Show groups? | Show left groups? |
| --------------------------------------------------------------------- | ------------------------------------------- | ------------------------ | ------------------------ |
| Various group member pickers (adding members, group story recipients) | `BaseMemberViewController` | No | N/A |
| Send payment screen | `PaymentsSendRecipientViewController` | No | N/A |
| Gift badging “choose recipient” screen | `BadgeGiftingChooseRecipientViewController` | No | N/A |
| Composer | `ComposeViewController` | Yes, only when searching | No |
| Add to block list (in Settings → Privacy) | `AddToBlockListViewController` | Yes, only when searching | Yes, only when searching |
| Share sheet | `SharingThreadPickerViewController` | Yes | No |
| Message forwarding | `ForwardMessageViewController` | Yes | No |
| In-app camera | `CameraFirstCaptureSendFlow` | Yes | No |
| Share group link via Signal | `GroupLinkViewController` | Yes | No |
| Share sticker pack, from in a chat | `StickerPackViewController` | Yes | No |
| Share sticker pack, from sticker management screen | `ManageStickersViewController` | Yes | No |
| “New Group Story” screen | `NewGroupStoryViewController` | Yes (exclusively) | No |
This doesn't intend to change the behavior of *deleted* groups. Those
will show up when searching if groups are shown at all. For example, a
deleted group will show in the composer if you search for it just like
any other group. A deleted group will *not* show in the "send payment"
screen because groups are never shown there. Again, the behavior around
deleted groups should remain unchanged.
Co-authored-by: Max Radermacher <max@signal.org>
