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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1 files changed, 14 insertions, 17 deletions

diff --git a/components/script/dom/htmlvideoelement.rs b/components/script/dom/htmlvideoelement.rs
index f83c05bbe0a..a890b49af72 100644
--- a/components/script/dom/htmlvideoelement.rs
+++ b/components/script/dom/htmlvideoelement.rs
@@ -19,16 +19,17 @@ use crate::dom::node::{document_from_node, window_from_node, Node};
 use crate::dom::performanceresourcetiming::InitiatorType;
 use crate::dom::virtualmethods::VirtualMethods;
 use crate::fetch::FetchCanceller;
-use crate::image_listener::{add_cache_listener_for_element, ImageCacheListener};
+use crate::image_listener::{generate_cache_listener_for_element, ImageCacheListener};
 use crate::network_listener::{self, NetworkListener, PreInvoke, ResourceTimingListener};
 use dom_struct::dom_struct;
 use euclid::default::Size2D;
 use html5ever::{LocalName, Prefix};
 use ipc_channel::ipc;
 use ipc_channel::router::ROUTER;
-use net_traits::image_cache::UsePlaceholder;
-use net_traits::image_cache::{CanRequestImages, ImageCache, ImageOrMetadataAvailable};
-use net_traits::image_cache::{ImageResponse, ImageState, PendingImageId};
+use net_traits::image_cache::{
+    CanRequestImages, ImageCache, ImageCacheResult, ImageOrMetadataAvailable, ImageResponse,
+    PendingImageId, UsePlaceholder,
+};
 use net_traits::request::{CredentialsMode, Destination, RequestBuilder};
 use net_traits::{
     CoreResourceMsg, FetchChannels, FetchMetadata, FetchResponseListener, FetchResponseMsg,
@@ -155,27 +156,23 @@ impl HTMLVideoElement {
         // network activity as possible.
         let window = window_from_node(self);
         let image_cache = window.image_cache();
-        let response = image_cache.find_image_or_metadata(
-            poster_url.clone().into(),
+        let sender = generate_cache_listener_for_element(self);
+        let cache_result = image_cache.track_image(
+            poster_url.clone(),
             window.origin().immutable().clone(),
             None,
+            sender,
             UsePlaceholder::No,
             CanRequestImages::Yes,
         );
-        match response {
-            Ok(ImageOrMetadataAvailable::ImageAvailable(image, url)) => {
-                self.process_image_response(ImageResponse::Loaded(image, url));
-            },
 
-            Err(ImageState::Pending(id)) => {
-                add_cache_listener_for_element(image_cache, id, self);
+        match cache_result {
+            ImageCacheResult::Available(ImageOrMetadataAvailable::ImageAvailable(img, url)) => {
+                self.process_image_response(ImageResponse::Loaded(img, url));
             },
-
-            Err(ImageState::NotRequested(id)) => {
-                add_cache_listener_for_element(image_cache, id, self);
-                self.do_fetch_poster_frame(poster_url, id, cancel_receiver);
+            ImageCacheResult::ReadyForRequest(id) => {
+                self.do_fetch_poster_frame(poster_url, id, cancel_receiver)
             },
-
             _ => (),
         }
     }