Add Linux platform, gate usage of CVImageBuffer by macOS

crates/gpui/src/elements/img.rs

@@ -7,6 +7,7 @@ use crate::{
     StyleRefinement, Styled, UriOrPath,
 };
 use futures::FutureExt;
+#[cfg(target_os = "macos")]
 use media::core_video::CVImageBuffer;
 use util::ResultExt;
 
@@ -21,6 +22,7 @@ pub enum ImageSource {
     Data(Arc<ImageData>),
     // TODO: move surface definitions into mac platform module
     /// A CoreVideo image buffer
+    #[cfg(target_os = "macos")]
     Surface(CVImageBuffer),
 }
 
@@ -54,6 +56,7 @@ impl From<Arc<ImageData>> for ImageSource {
     }
 }
 
+#[cfg(target_os = "macos")]
 impl From<CVImageBuffer> for ImageSource {
     fn from(value: CVImageBuffer) -> Self {
         Self::Surface(value)
@@ -144,6 +147,7 @@ impl Element for Img {
                                 .log_err();
                         }
 
+                        #[cfg(target_os = "macos")]
                         ImageSource::Surface(surface) => {
                             let size = size(surface.width().into(), surface.height().into());
                             let new_bounds = preserve_aspect_ratio(bounds, size);