Move PopoverButton into ui (#25724)

This PR moves the `PopoverButton` component into the `ui` crate.

The `popover_button` crate only depended on `ui`, so there doesn't seem
to be a need for it to live in its own crate and add another step in the
crate graph.

Release Notes:

- N/A

crates/ui/src/components.rs

@@ -19,6 +19,7 @@ mod modal;
 mod navigable;
 mod numeric_stepper;
 mod popover;
+mod popover_button;
 mod popover_menu;
 mod radio;
 mod right_click_menu;
@@ -56,6 +57,7 @@ pub use modal::*;
 pub use navigable::*;
 pub use numeric_stepper::*;
 pub use popover::*;
+pub use popover_button::*;
 pub use popover_menu::*;
 pub use radio::*;
 pub use right_click_menu::*;

crates/ui/src/components/popover_button.rs

@@ -0,0 +1,57 @@
+use gpui::{AnyView, Corner, Entity, ManagedView};
+
+use crate::{prelude::*, PopoverMenu, PopoverMenuHandle, PopoverTrigger};
+
+pub trait TriggerablePopover: ManagedView {
+    fn menu_handle(
+        &mut self,
+        window: &mut Window,
+        cx: &mut gpui::Context<Self>,
+    ) -> PopoverMenuHandle<Self>;
+}
+
+pub struct PopoverButton<T, B, F> {
+    selector: Entity<T>,
+    button: B,
+    tooltip: F,
+    corner: Corner,
+}
+
+impl<T, B, F> PopoverButton<T, B, F> {
+    pub fn new(selector: Entity<T>, corner: Corner, button: B, tooltip: F) -> Self
+    where
+        F: Fn(&mut Window, &mut App) -> AnyView + 'static,
+    {
+        Self {
+            selector,
+            button,
+            tooltip,
+            corner,
+        }
+    }
+}
+
+impl<T: TriggerablePopover, B: PopoverTrigger + ButtonCommon, F> RenderOnce
+    for PopoverButton<T, B, F>
+where
+    F: Fn(&mut Window, &mut App) -> AnyView + 'static,
+{
+    fn render(self, window: &mut Window, cx: &mut App) -> impl IntoElement {
+        let menu_handle = self
+            .selector
+            .update(cx, |selector, cx| selector.menu_handle(window, cx));
+
+        PopoverMenu::new("popover-button")
+            .menu({
+                let selector = self.selector.clone();
+                move |_window, _cx| Some(selector.clone())
+            })
+            .trigger_with_tooltip(self.button, self.tooltip)
+            .anchor(self.corner)
+            .with_handle(menu_handle)
+            .offset(gpui::Point {
+                x: px(0.0),
+                y: px(-2.0),
+            })
+    }
+}