Auto merge of #23848 - asajeffrey:webxr-moar-channels, r=Manishearth

Replace use of callbacks in webxr by channels

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Use senders rather than callbacks in webxr.

---
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- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because it's an internal change

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4 files changed, 17 insertions, 86 deletions

diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 743a2adec84..3a273f3cfa3 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -328,6 +328,10 @@ impl WebGLRenderingContext {
         self.webgl_sender.clone()
     }
 
+    pub fn context_id(&self) -> WebGLContextId {
+        self.webgl_sender.context_id()
+    }
+
     #[inline]
     pub fn send_command(&self, command: WebGLCommand) {
         self.webgl_sender
@@ -4377,8 +4381,4 @@ impl WebGLMessageSender {
     pub fn send_dom_to_texture(&self, command: DOMToTextureCommand) -> WebGLSendResult {
         self.wake_after_send(|| self.sender.send_dom_to_texture(command))
     }
-
-    pub fn webxr_external_image_api(&self) -> impl webxr_api::WebGLExternalImageApi {
-        self.sender.webxr_external_image_api()
-    }
 }
diff --git a/components/script/dom/xr.rs b/components/script/dom/xr.rs
index d24e8f144cd..8deead58b92 100644
--- a/components/script/dom/xr.rs
+++ b/components/script/dom/xr.rs
@@ -108,18 +108,6 @@ impl Into<SessionMode> for XRSessionMode {
 impl XRMethods for XR {
     /// https://immersive-web.github.io/webxr/#dom-xr-supportssessionmode
     fn SupportsSession(&self, mode: XRSessionMode) -> Rc<Promise> {
-        #[derive(serde::Serialize, serde::Deserialize)]
-        pub struct SupportsSession {
-            sender: IpcSender<bool>,
-        }
-
-        #[typetag::serde]
-        impl webxr_api::SessionSupportCallback for SupportsSession {
-            fn callback(&mut self, result: Result<(), XRError>) {
-                let _ = self.sender.send(result.is_ok());
-            }
-        }
-
         // XXXManishearth this should select an XR device first
         let promise = Promise::new(&self.global());
         let mut trusted = Some(TrustedPromise::new(promise.clone()));
@@ -139,13 +127,13 @@ impl XRMethods for XR {
                     error!("supportsSession callback called twice!");
                     return;
                 };
-                let message = if let Ok(message) = message.to() {
+                let message: Result<(), webxr_api::Error> = if let Ok(message) = message.to() {
                     message
                 } else {
                     error!("supportsSession callback given incorrect payload");
                     return;
                 };
-                if message {
+                if let Ok(()) = message {
                     let _ = task_source.queue_with_canceller(trusted.resolve_task(()), &canceller);
                 } else {
                     let _ = task_source
@@ -155,7 +143,7 @@ impl XRMethods for XR {
         );
         window
             .webxr_registry()
-            .supports_session(mode.into(), SupportsSession { sender });
+            .supports_session(mode.into(), sender);
 
         promise
     }
@@ -167,17 +155,6 @@ impl XRMethods for XR {
         _: &XRSessionInit,
         comp: InCompartment,
     ) -> Rc<Promise> {
-        #[derive(serde::Serialize, serde::Deserialize)]
-        pub struct RequestSession {
-            sender: IpcSender<Result<Session, XRError>>,
-        }
-
-        #[typetag::serde]
-        impl webxr_api::SessionRequestCallback for RequestSession {
-            fn callback(&mut self, result: Result<Session, XRError>) {
-                let _ = self.sender.send(result);
-            }
-        }
         let promise = Promise::new_in_current_compartment(&self.global(), comp);
         if mode != XRSessionMode::Immersive_vr {
             promise.reject_error(Error::NotSupported);
@@ -206,7 +183,7 @@ impl XRMethods for XR {
                 // router doesn't know this is only called once
                 let trusted = trusted.take().unwrap();
                 let this = this.clone();
-                let message = if let Ok(message) = message.to() {
+                let message: Result<Session, webxr_api::Error> = if let Ok(message) = message.to() {
                     message
                 } else {
                     error!("requestSession callback given incorrect payload");
@@ -220,9 +197,7 @@ impl XRMethods for XR {
                 );
             }),
         );
-        window
-            .webxr_registry()
-            .request_session(mode.into(), RequestSession { sender });
+        window.webxr_registry().request_session(mode.into(), sender);
 
         promise
     }
diff --git a/components/script/dom/xrsession.rs b/components/script/dom/xrsession.rs
index 9542486f3ae..0a9712bb92b 100644
--- a/components/script/dom/xrsession.rs
+++ b/components/script/dom/xrsession.rs
@@ -124,18 +124,6 @@ impl XRSession {
     }
 
     fn attach_event_handler(&self) {
-        #[derive(serde::Serialize, serde::Deserialize)]
-        pub struct EventCallback {
-            sender: IpcSender<XREvent>,
-        }
-
-        #[typetag::serde]
-        impl webxr_api::EventCallback for EventCallback {
-            fn callback(&mut self, event: XREvent) {
-                let _ = self.sender.send(event);
-            }
-        }
-
         let this = Trusted::new(self);
         let global = self.global();
         let window = global.as_window();
@@ -143,6 +131,7 @@ impl XRSession {
             .task_manager()
             .dom_manipulation_task_source_with_canceller();
         let (sender, receiver) = ipc::channel(global.time_profiler_chan().clone()).unwrap();
+
         ROUTER.add_route(
             receiver.to_opaque(),
             Box::new(move |message| {
@@ -157,9 +146,7 @@ impl XRSession {
         );
 
         // request animation frame
-        self.session
-            .borrow_mut()
-            .set_event_callback(EventCallback { sender });
+        self.session.borrow_mut().set_event_dest(sender);
     }
 
     fn event_callback(&self, event: XREvent) {
@@ -195,13 +182,10 @@ impl XRSession {
             // Step 6-7: XXXManishearth handle inlineVerticalFieldOfView
 
             // XXXManishearth handle inline sessions and composition disabled flag
-            let layer = pending.GetBaseLayer();
-            if let Some(layer) = layer {
-                let mut session = self.session.borrow_mut();
-                session.update_webgl_external_image_api(
-                    layer.Context().webgl_sender().webxr_external_image_api(),
-                );
-            }
+            let context = pending
+                .GetBaseLayer()
+                .map(|layer| layer.Context().context_id().0);
+            self.session.borrow_mut().set_webgl_context(context);
         }
 
         // Step 2
@@ -289,18 +273,6 @@ impl XRSessionMethods for XRSession {
 
     /// https://immersive-web.github.io/webxr/#dom-xrsession-requestanimationframe
     fn RequestAnimationFrame(&self, callback: Rc<XRFrameRequestCallback>) -> i32 {
-        #[derive(serde::Serialize, serde::Deserialize)]
-        pub struct FrameCallback {
-            sender: IpcSender<(f64, Frame)>,
-        }
-
-        #[typetag::serde]
-        impl webxr_api::FrameRequestCallback for FrameCallback {
-            fn callback(&mut self, time: f64, frame: Frame) {
-                let _ = self.sender.send((time, frame));
-            }
-        }
-
         // queue up RAF callback, obtain ID
         let raf_id = self.next_raf_id.get();
         self.next_raf_id.set(raf_id + 1);
@@ -334,9 +306,7 @@ impl XRSessionMethods for XRSession {
         let sender = self.raf_sender.borrow().clone().unwrap();
 
         // request animation frame
-        self.session
-            .borrow_mut()
-            .request_animation_frame(FrameCallback { sender });
+        self.session.borrow_mut().request_animation_frame(sender);
 
         raf_id
     }
diff --git a/components/script/dom/xrtest.rs b/components/script/dom/xrtest.rs
index c8f45b75b4f..3c376366faf 100644
--- a/components/script/dom/xrtest.rs
+++ b/components/script/dom/xrtest.rs
@@ -73,20 +73,6 @@ impl XRTest {
 impl XRTestMethods for XRTest {
     /// https://github.com/immersive-web/webxr-test-api/blob/master/explainer.md
     fn SimulateDeviceConnection(&self, init: &FakeXRDeviceInit) -> Rc<Promise> {
-        #[derive(serde::Serialize, serde::Deserialize)]
-        pub struct MockDevice {
-            sender: IpcSender<Result<IpcSender<MockDeviceMsg>, XRError>>,
-        }
-
-        #[typetag::serde]
-        impl webxr_api::MockDeviceCallback for MockDevice {
-            fn callback(&mut self, result: Result<IpcSender<MockDeviceMsg>, XRError>) {
-                self.sender
-                    .send(result)
-                    .expect("mock device callback failed");
-            }
-        }
-
         let p = Promise::new(&self.global());
 
         if !init.supportsImmersive || self.session_started.get() {
@@ -166,7 +152,7 @@ impl XRTestMethods for XRTest {
         );
         window
             .webxr_registry()
-            .simulate_device_connection(init, MockDevice { sender });
+            .simulate_device_connection(init, sender);
 
         p
     }