Eliminate GPUI View, ViewContext, and WindowContext types (#22632)

There's still a bit more work to do on this, but this PR is compiling
(with warnings) after eliminating the key types. When the tasks below
are complete, this will be the new narrative for GPUI:

- `Entity<T>` - This replaces `View<T>`/`Model<T>`. It represents a unit
of state, and if `T` implements `Render`, then `Entity<T>` implements
`Element`.
- `&mut App` This replaces `AppContext` and represents the app.
- `&mut Context<T>` This replaces `ModelContext` and derefs to `App`. It
is provided by the framework when updating an entity.
- `&mut Window` Broken out of `&mut WindowContext` which no longer
exists. Every method that once took `&mut WindowContext` now takes `&mut
Window, &mut App` and every method that took `&mut ViewContext<T>` now
takes `&mut Window, &mut Context<T>`

Not pictured here are the two other failed attempts. It's been quite a
month!

Tasks:

- [x] Remove `View`, `ViewContext`, `WindowContext` and thread through
`Window`
- [x] [@cole-miller @mikayla-maki] Redraw window when entities change
- [x] [@cole-miller @mikayla-maki] Get examples and Zed running
- [x] [@cole-miller @mikayla-maki] Fix Zed rendering
- [x] [@mikayla-maki] Fix todo! macros and comments
- [x] Fix a bug where the editor would not be redrawn because of view
caching
- [x] remove publicness window.notify() and replace with
`AppContext::notify`
- [x] remove `observe_new_window_models`, replace with
`observe_new_models` with an optional window
- [x] Fix a bug where the project panel would not be redrawn because of
the wrong refresh() call being used
- [x] Fix the tests
- [x] Fix warnings by eliminating `Window` params or using `_`
- [x] Fix conflicts
- [x] Simplify generic code where possible
- [x] Rename types
- [ ] Update docs

### issues post merge

- [x] Issues switching between normal and insert mode
- [x] Assistant re-rendering failure
- [x] Vim test failures
- [x] Mac build issue



Release Notes:

- N/A

---------

Co-authored-by: Antonio Scandurra <me@as-cii.com>
Co-authored-by: Cole Miller <cole@zed.dev>
Co-authored-by: Mikayla <mikayla@zed.dev>
Co-authored-by: Joseph <joseph@zed.dev>
Co-authored-by: max <max@zed.dev>
Co-authored-by: Michael Sloan <michael@zed.dev>
Co-authored-by: Mikayla Maki <mikaylamaki@Mikaylas-MacBook-Pro.local>
Co-authored-by: Mikayla <mikayla.c.maki@gmail.com>
Co-authored-by: joão <joao@zed.dev>

crates/extensions_ui/src/extension_version_selector.rs

@@ -5,9 +5,7 @@ use client::ExtensionMetadata;
 use extension_host::{ExtensionSettings, ExtensionStore};
 use fs::Fs;
 use fuzzy::{match_strings, StringMatch, StringMatchCandidate};
-use gpui::{
-    prelude::*, AppContext, DismissEvent, EventEmitter, FocusableView, Task, View, WeakView,
-};
+use gpui::{prelude::*, App, DismissEvent, Entity, EventEmitter, Focusable, Task, WeakEntity};
 use picker::{Picker, PickerDelegate};
 use release_channel::ReleaseChannel;
 use semantic_version::SemanticVersion;
@@ -17,35 +15,39 @@ use util::ResultExt;
 use workspace::ModalView;
 
 pub struct ExtensionVersionSelector {
-    picker: View<Picker<ExtensionVersionSelectorDelegate>>,
+    picker: Entity<Picker<ExtensionVersionSelectorDelegate>>,
 }
 
 impl ModalView for ExtensionVersionSelector {}
 
 impl EventEmitter<DismissEvent> for ExtensionVersionSelector {}
 
-impl FocusableView for ExtensionVersionSelector {
-    fn focus_handle(&self, cx: &AppContext) -> gpui::FocusHandle {
+impl Focusable for ExtensionVersionSelector {
+    fn focus_handle(&self, cx: &App) -> gpui::FocusHandle {
         self.picker.focus_handle(cx)
     }
 }
 
 impl Render for ExtensionVersionSelector {
-    fn render(&mut self, _cx: &mut ViewContext<Self>) -> impl IntoElement {
+    fn render(&mut self, _window: &mut Window, _cx: &mut Context<Self>) -> impl IntoElement {
         v_flex().w(rems(34.)).child(self.picker.clone())
     }
 }
 
 impl ExtensionVersionSelector {
-    pub fn new(delegate: ExtensionVersionSelectorDelegate, cx: &mut ViewContext<Self>) -> Self {
-        let picker = cx.new_view(|cx| Picker::uniform_list(delegate, cx));
+    pub fn new(
+        delegate: ExtensionVersionSelectorDelegate,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> Self {
+        let picker = cx.new(|cx| Picker::uniform_list(delegate, window, cx));
         Self { picker }
     }
 }
 
 pub struct ExtensionVersionSelectorDelegate {
     fs: Arc<dyn Fs>,
-    view: WeakView<ExtensionVersionSelector>,
+    selector: WeakEntity<ExtensionVersionSelector>,
     extension_versions: Vec<ExtensionMetadata>,
     selected_index: usize,
     matches: Vec<StringMatch>,
@@ -54,7 +56,7 @@ pub struct ExtensionVersionSelectorDelegate {
 impl ExtensionVersionSelectorDelegate {
     pub fn new(
         fs: Arc<dyn Fs>,
-        weak_view: WeakView<ExtensionVersionSelector>,
+        selector: WeakEntity<ExtensionVersionSelector>,
         mut extension_versions: Vec<ExtensionMetadata>,
     ) -> Self {
         extension_versions.sort_unstable_by(|a, b| {
@@ -79,7 +81,7 @@ impl ExtensionVersionSelectorDelegate {
 
         Self {
             fs,
-            view: weak_view,
+            selector,
             extension_versions,
             selected_index: 0,
             matches,
@@ -90,7 +92,7 @@ impl ExtensionVersionSelectorDelegate {
 impl PickerDelegate for ExtensionVersionSelectorDelegate {
     type ListItem = ui::ListItem;
 
-    fn placeholder_text(&self, _cx: &mut WindowContext) -> Arc<str> {
+    fn placeholder_text(&self, _window: &mut Window, _cx: &mut App) -> Arc<str> {
         "Select extension version...".into()
     }
 
@@ -102,11 +104,21 @@ impl PickerDelegate for ExtensionVersionSelectorDelegate {
         self.selected_index
     }
 
-    fn set_selected_index(&mut self, ix: usize, _cx: &mut ViewContext<Picker<Self>>) {
+    fn set_selected_index(
+        &mut self,
+        ix: usize,
+        _window: &mut Window,
+        _cx: &mut Context<Picker<Self>>,
+    ) {
         self.selected_index = ix;
     }
 
-    fn update_matches(&mut self, query: String, cx: &mut ViewContext<Picker<Self>>) -> Task<()> {
+    fn update_matches(
+        &mut self,
+        query: String,
+        window: &mut Window,
+        cx: &mut Context<Picker<Self>>,
+    ) -> Task<()> {
         let background_executor = cx.background_executor().clone();
         let candidates = self
             .extension_versions
@@ -117,7 +129,7 @@ impl PickerDelegate for ExtensionVersionSelectorDelegate {
             })
             .collect::<Vec<_>>();
 
-        cx.spawn(move |this, mut cx| async move {
+        cx.spawn_in(window, move |this, mut cx| async move {
             let matches = if query.is_empty() {
                 candidates
                     .into_iter()
@@ -152,9 +164,9 @@ impl PickerDelegate for ExtensionVersionSelectorDelegate {
         })
     }
 
-    fn confirm(&mut self, _secondary: bool, cx: &mut ViewContext<Picker<Self>>) {
+    fn confirm(&mut self, _secondary: bool, window: &mut Window, cx: &mut Context<Picker<Self>>) {
         if self.matches.is_empty() {
-            self.dismissed(cx);
+            self.dismissed(window, cx);
             return;
         }
 
@@ -181,8 +193,8 @@ impl PickerDelegate for ExtensionVersionSelectorDelegate {
         });
     }
 
-    fn dismissed(&mut self, cx: &mut ViewContext<Picker<Self>>) {
-        self.view
+    fn dismissed(&mut self, _: &mut Window, cx: &mut Context<Picker<Self>>) {
+        self.selector
             .update(cx, |_, cx| cx.emit(DismissEvent))
             .log_err();
     }
@@ -191,7 +203,8 @@ impl PickerDelegate for ExtensionVersionSelectorDelegate {
         &self,
         ix: usize,
         selected: bool,
-        cx: &mut ViewContext<Picker<Self>>,
+        _: &mut Window,
+        cx: &mut Context<Picker<Self>>,
     ) -> Option<Self::ListItem> {
         let version_match = &self.matches[ix];
         let extension_version = &self.extension_versions[version_match.candidate_id];