Auto merge of #23661 - julientregoat:i-21289, r=jdm

Refactor ImageCache::find_image_or_metadata -> ImageCache::{get_image, track_image}

<!-- Please describe your changes on the following line: -->
Updated the `ImageCache` trait to replace `find_image_or_metadata` with two new functions `track_image` and `get_image`, as well as a new enum (`ImageCacheResult`).

As a result, I was able to refactor the functions that previously called `find_image_or_metadata` pretty cleanly. For a list of these functions, please see the commit information.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #21289  (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because tests already exist for these components. I ran `cargo test` in `net`, `net_traits`, `layout`, and `script` successfully.

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components/script/dom/htmlcanvaselement.rs

@@ -432,8 +432,7 @@ impl<'a> From<&'a WebGLContextAttributes> for GLContextAttributes {
 
 pub mod utils {
     use crate::dom::window::Window;
-    use net_traits::image_cache::CanRequestImages;
-    use net_traits::image_cache::{ImageOrMetadataAvailable, ImageResponse, UsePlaceholder};
+    use net_traits::image_cache::ImageResponse;
     use net_traits::request::CorsSettings;
     use servo_url::ServoUrl;
 
@@ -443,18 +442,15 @@ pub mod utils {
         cors_setting: Option<CorsSettings>,
     ) -> ImageResponse {
         let image_cache = window.image_cache();
-        let response = image_cache.find_image_or_metadata(
-            url.into(),
+        let result = image_cache.get_image(
+            url.clone(),
             window.origin().immutable().clone(),
             cors_setting,
-            UsePlaceholder::No,
-            CanRequestImages::No,
         );
-        match response {
-            Ok(ImageOrMetadataAvailable::ImageAvailable(image, url)) => {
-                ImageResponse::Loaded(image, url)
-            },
-            _ => ImageResponse::None,
+
+        match result {
+            Some(image) => ImageResponse::Loaded(image, url),
+            None => ImageResponse::None,
         }
     }
 }