Allow modals to override their dismissal (#3565)

Release Notes:

- N/A

crates/collab_ui2/src/collab_panel/channel_modal.rs

@@ -13,6 +13,7 @@ use picker::{Picker, PickerDelegate};
 use std::sync::Arc;
 use ui::prelude::*;
 use util::TryFutureExt;
+use workspace::ModalView;
 
 actions!(
     SelectNextControl,
@@ -140,6 +141,7 @@ impl ChannelModal {
 }
 
 impl EventEmitter<DismissEvent> for ChannelModal {}
+impl ModalView for ChannelModal {}
 
 impl FocusableView for ChannelModal {
     fn focus_handle(&self, cx: &AppContext) -> gpui::FocusHandle {

crates/collab_ui2/src/collab_panel/contact_finder.rs

@@ -9,6 +9,7 @@ use std::sync::Arc;
 use theme::ActiveTheme as _;
 use ui::prelude::*;
 use util::{ResultExt as _, TryFutureExt};
+use workspace::ModalView;
 
 pub fn init(cx: &mut AppContext) {
     //Picker::<ContactFinderDelegate>::init(cx);
@@ -95,6 +96,7 @@ pub struct ContactFinderDelegate {
 }
 
 impl EventEmitter<DismissEvent> for ContactFinder {}
+impl ModalView for ContactFinder {}
 
 impl FocusableView for ContactFinder {
     fn focus_handle(&self, cx: &AppContext) -> FocusHandle {