No tracing of nop traceable fields (#29926)

* Add `no_trace` option to JSTraceable derive

* NoTrace wrapper

* Port some types to no_trace schematics

* Fixing my unsafe mistakes (not tracing traceables)

* Add docs & safety guards for no_trace

Safety guards (trait shenanigans) guarantees safety usage of `no_trace`

* Port canvas_traits to no_trace

* Port servo_media to no_trace

* Port net_traits to no_trace

* Port style to no_trace

* Port webgpu to no_trace

* Port script_traits to no_trace

* Port canvas_traits, devtools_traits, embedder_traits, profile_traits to no_trace

* unrooted_must_root lint in seperate file

* Add trace_in_no_trace_lint as script_plugin

* Composable types in must_not_have_traceable

* Introduced HashMapTracedValues wrapper

* `HashMap<NoTrace<K>,V>`->`HashMapTracedValues<K,V>`

* Port rest of servo's types to no_trace

* Port html5ever, euclid, mime and http to no_trace

* Port remaining externals to no_trace

* Port webxr and Arc<Mutex<_>>

* Fix spelling in notrace doc

1 files changed, 4 insertions, 0 deletions

diff --git a/components/script/dom/htmlimageelement.rs b/components/script/dom/htmlimageelement.rs
index 1598dbd7e2d..cd6e27537e5 100644
--- a/components/script/dom/htmlimageelement.rs
+++ b/components/script/dom/htmlimageelement.rs
@@ -142,12 +142,16 @@ enum ImageRequestPhase {
 #[unrooted_must_root_lint::must_root]
 struct ImageRequest {
     state: State,
+    #[no_trace]
     parsed_url: Option<ServoUrl>,
     source_url: Option<USVString>,
     blocker: Option<LoadBlocker>,
     #[ignore_malloc_size_of = "Arc"]
+    #[no_trace]
     image: Option<Arc<Image>>,
+    #[no_trace]
     metadata: Option<ImageMetadata>,
+    #[no_trace]
     final_url: Option<ServoUrl>,
     current_pixel_density: Option<f64>,
 }