Auto merge of #24340 - jdm:image-cache-cors, r=Manishearth

Allow using CORS filtered image responses as WebGL textures

More specifically, this makes the "is this image same origin?" check consider the CORS status of the original response, rather than relying on an overly-strict "is this image's response's URL same-origin with a particular global?" check. To do this, we make the image cache double keyed based on the requested URL as well as the requesting origin, and store the CORS status of the eventual response with the final image that eventually gets sent to the HTMLImageElement consumer.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #24330 and fix #24368
- [x] There are tests for these changes

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1 files changed, 10 insertions, 2 deletions

diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index 4b16db4699e..baf4fcd0878 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -35,7 +35,7 @@ use crate::dom::create::create_element;
 use crate::dom::customelementregistry::{
     CallbackReaction, CustomElementDefinition, CustomElementReaction, CustomElementState,
 };
-use crate::dom::document::{Document, LayoutDocumentHelpers};
+use crate::dom::document::{determine_policy_for_token, Document, LayoutDocumentHelpers};
 use crate::dom::documentfragment::DocumentFragment;
 use crate::dom::domrect::DOMRect;
 use crate::dom::domtokenlist::DOMTokenList;
@@ -97,6 +97,7 @@ use js::jsapi::Heap;
 use js::jsval::JSVal;
 use msg::constellation_msg::InputMethodType;
 use net_traits::request::CorsSettings;
+use net_traits::ReferrerPolicy;
 use ref_filter_map::ref_filter_map;
 use script_layout_interface::message::ReflowGoal;
 use selectors::attr::{AttrSelectorOperation, CaseSensitivity, NamespaceConstraint};
@@ -3606,7 +3607,14 @@ pub fn set_cross_origin_attribute(element: &Element, value: Option<DOMString>) {
     }
 }
 
-pub fn cors_setting_for_element(element: &Element) -> Option<CorsSettings> {
+pub(crate) fn referrer_policy_for_element(element: &Element) -> Option<ReferrerPolicy> {
+    element
+        .get_attribute_by_name(DOMString::from_string(String::from("referrerpolicy")))
+        .and_then(|attribute: DomRoot<Attr>| determine_policy_for_token(&attribute.Value()))
+        .or_else(|| document_from_node(element).get_referrer_policy())
+}
+
+pub(crate) fn cors_setting_for_element(element: &Element) -> Option<CorsSettings> {
     reflect_cross_origin_attribute(element).map_or(None, |attr| match &*attr {
         "anonymous" => Some(CorsSettings::Anonymous),
         "use-credentials" => Some(CorsSettings::UseCredentials),