Extract canvas operations for reuse by OffscreenCanvas.

1 files changed, 15 insertions, 0 deletions

diff --git a/components/script/dom/globalscope.rs b/components/script/dom/globalscope.rs
index f803d6228b7..1330021035a 100644
--- a/components/script/dom/globalscope.rs
+++ b/components/script/dom/globalscope.rs
@@ -20,6 +20,7 @@ use crate::dom::errorevent::ErrorEvent;
 use crate::dom::event::{Event, EventBubbles, EventCancelable, EventStatus};
 use crate::dom::eventsource::EventSource;
 use crate::dom::eventtarget::EventTarget;
+use crate::dom::paintworkletglobalscope::PaintWorkletGlobalScope;
 use crate::dom::performance::Performance;
 use crate::dom::window::Window;
 use crate::dom::workerglobalscope::WorkerGlobalScope;
@@ -51,6 +52,7 @@ use js::rust::{get_object_class, CompileOptionsWrapper, ParentRuntime, Runtime};
 use js::rust::{HandleValue, MutableHandleValue};
 use js::{JSCLASS_IS_DOMJSCLASS, JSCLASS_IS_GLOBAL};
 use msg::constellation_msg::PipelineId;
+use net_traits::image_cache::ImageCache;
 use net_traits::{CoreResourceThread, IpcSend, ResourceThreads};
 use profile_traits::{mem as profile_mem, time as profile_time};
 use script_traits::{MsDuration, ScriptToConstellationChan, TimerEvent};
@@ -376,6 +378,19 @@ impl GlobalScope {
         &self.origin
     }
 
+    pub fn image_cache(&self) -> Arc<dyn ImageCache> {
+        if let Some(window) = self.downcast::<Window>() {
+            return window.image_cache();
+        }
+        if let Some(worker) = self.downcast::<DedicatedWorkerGlobalScope>() {
+            return worker.image_cache();
+        }
+        if let Some(worker) = self.downcast::<PaintWorkletGlobalScope>() {
+            return worker.image_cache();
+        }
+        unreachable!();
+    }
+
     /// Get the [base url](https://html.spec.whatwg.org/multipage/#api-base-url)
     /// for this global scope.
     pub fn api_base_url(&self) -> ServoUrl {