Add the ability to render icons as indicators (#11273)

This PR adds the ability to render `Icon`s as an `Indicator`.

Release Notes:

- N/A

Co-authored-by: Nate Butler <nate@zed.dev>

crates/ui/src/components/icon.rs

@@ -1,8 +1,46 @@
-use gpui::{svg, Hsla, IntoElement, Rems, Transformation};
+use gpui::{svg, AnimationElement, Hsla, IntoElement, Rems, Transformation};
 use strum::EnumIter;
 
 use crate::{prelude::*, Indicator};
 
+#[derive(IntoElement)]
+pub enum AnyIcon {
+    Icon(Icon),
+    AnimatedIcon(AnimationElement<Icon>),
+}
+
+impl AnyIcon {
+    /// Returns a new [`AnyIcon`] after applying the given mapping function
+    /// to the contained [`Icon`].
+    pub fn map(self, f: impl FnOnce(Icon) -> Icon) -> Self {
+        match self {
+            Self::Icon(icon) => Self::Icon(f(icon)),
+            Self::AnimatedIcon(animated_icon) => Self::AnimatedIcon(animated_icon.map_element(f)),
+        }
+    }
+}
+
+impl From<Icon> for AnyIcon {
+    fn from(value: Icon) -> Self {
+        Self::Icon(value)
+    }
+}
+
+impl From<AnimationElement<Icon>> for AnyIcon {
+    fn from(value: AnimationElement<Icon>) -> Self {
+        Self::AnimatedIcon(value)
+    }
+}
+
+impl RenderOnce for AnyIcon {
+    fn render(self, _cx: &mut WindowContext) -> impl IntoElement {
+        match self {
+            Self::Icon(icon) => icon.into_any_element(),
+            Self::AnimatedIcon(animated_icon) => animated_icon.into_any_element(),
+        }
+    }
+}
+
 #[derive(Default, PartialEq, Copy, Clone)]
 pub enum IconSize {
     Indicator,
@@ -236,7 +274,7 @@ impl IconName {
 pub struct Icon {
     path: SharedString,
     color: Color,
-    size: IconSize,
+    size: Rems,
     transformation: Transformation,
 }
 
@@ -245,7 +283,7 @@ impl Icon {
         Self {
             path: icon.path().into(),
             color: Color::default(),
-            size: IconSize::default(),
+            size: IconSize::default().rems(),
             transformation: Transformation::default(),
         }
     }
@@ -254,7 +292,7 @@ impl Icon {
         Self {
             path: path.into(),
             color: Color::default(),
-            size: IconSize::default(),
+            size: IconSize::default().rems(),
             transformation: Transformation::default(),
         }
     }
@@ -265,6 +303,14 @@ impl Icon {
     }
 
     pub fn size(mut self, size: IconSize) -> Self {
+        self.size = size.rems();
+        self
+    }
+
+    /// Sets a custom size for the icon, in [`Rems`].
+    ///
+    /// Not to be exposed outside of the `ui` crate.
+    pub(crate) fn custom_size(mut self, size: Rems) -> Self {
         self.size = size;
         self
     }
@@ -279,7 +325,7 @@ impl RenderOnce for Icon {
     fn render(self, cx: &mut WindowContext) -> impl IntoElement {
         svg()
             .with_transformation(self.transformation)
-            .size(self.size.rems())
+            .size(self.size)
             .flex_none()
             .path(self.path)
             .text_color(self.color.color(cx))