Fix sharp corners on images (#9408)

Release Notes:

- N/A

crates/gpui/src/platform/blade/shaders.wgsl

@@ -550,7 +550,7 @@ fn fs_poly_sprite(input: PolySpriteVarying) -> @location(0) vec4<f32> {
     }
 
     let sprite = b_poly_sprites[input.sprite_id];
-    let distance = quad_sdf(input.position.xy, sprite.content_mask, sprite.corner_radii);
+    let distance = quad_sdf(input.position.xy, sprite.bounds, sprite.corner_radii);
 
     var color = sample;
     if ((sprite.grayscale & 0xFFu) != 0u) {

crates/gpui/src/platform/mac/shaders.metal

@@ -372,7 +372,7 @@ fragment float4 polychrome_sprite_fragment(
   float4 sample =
       atlas_texture.sample(atlas_texture_sampler, input.tile_position);
   float distance =
-      quad_sdf(input.position.xy, sprite.content_mask.bounds, sprite.corner_radii);
+      quad_sdf(input.position.xy, sprite.bounds, sprite.corner_radii);
 
   float4 color = sample;
   if (sprite.grayscale) {