terminal/search: Partially fix search in terminal.

There are two issues with search in terminal as is:
- terminal's pane is not registered as a "legit" pane, so we dispatch buffer search bar::Deploy on the most recent "legit" pane. By legit I mean that
  workspace::active_pane will *never* return terminal pane as active.
- We've had the implementation of as_searchable commented out. Duh!

This commit fixes second issue. That means that if you drag the terminal over to the main editor pane (so that it's in a "legit" pane), it'll work. 1st issue still stands though.

Cargo.lock

@@ -7762,6 +7762,7 @@ dependencies = [
  "procinfo",
  "project",
  "rand 0.8.5",
+ "search",
  "serde",
  "serde_derive",
  "settings",

crates/terminal_view/Cargo.toml

@@ -13,7 +13,7 @@ editor = { path = "../editor" }
 language = { path = "../language" }
 gpui = { path = "../gpui" }
 project = { path = "../project" }
-# search = { path = "../search" }
+search = { path = "../search" }
 settings = { path = "../settings" }
 theme = { path = "../theme" }
 util = { path = "../util" }

crates/terminal_view/src/terminal_panel.rs

@@ -101,9 +101,9 @@ impl TerminalPanel {
                     })
                     .into_any_element()
             });
-            // let buffer_search_bar = cx.build_view(search::BufferSearchBar::new);
+            let buffer_search_bar = cx.add_view(search::BufferSearchBar::new);
-            // pane.toolbar()
+            pane.toolbar()
-            //     .update(cx, |toolbar, cx| toolbar.add_item(buffer_search_bar, cx));
+                .update(cx, |toolbar, cx| toolbar.add_item(buffer_search_bar, cx));
             pane
         });
         let subscriptions = vec![

crates/terminal_view/src/terminal_view.rs

@@ -28,7 +28,7 @@ use workspace::{
     item::{BreadcrumbText, Item, ItemEvent},
     notifications::NotifyResultExt,
     register_deserializable_item,
-    searchable::{SearchEvent, SearchOptions, SearchableItem},
+    searchable::{SearchEvent, SearchOptions, SearchableItem, SearchableItemHandle},
     CloseActiveItem, NewCenterTerminal, Pane, ToolbarItemLocation, Workspace, WorkspaceId,
 };
 
@@ -714,10 +714,9 @@ impl Item for TerminalView {
         false
     }
 
-    // todo!(search)
+    fn as_searchable(&self, handle: &View<Self>) -> Option<Box<dyn SearchableItemHandle>> {
-    // fn as_searchable(&self, handle: &View<Self>) -> Option<Box<dyn SearchableItemHandle>> {
+        Some(Box::new(handle.clone()))
-    //     Some(Box::new(handle.clone()))
+    }
-    // }
 
     fn breadcrumb_location(&self) -> ToolbarItemLocation {
         ToolbarItemLocation::PrimaryLeft