Auto merge of #23814 - Manishearth:events, r=asajeffrey

Partial support for events in WebXR

Needs https://github.com/servo/webxr/pull/20

r? @asajeffrey

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19 files changed, 299 insertions, 108 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 5213a915aa8..97f3f869cb8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5462,7 +5462,7 @@ dependencies = [
 [[package]]
 name = "webxr"
 version = "0.0.1"
-source = "git+https://github.com/servo/webxr#5c0eb61f8f38429fde45673d0884f947d14e9c79"
+source = "git+https://github.com/servo/webxr#b5a4b93fcfb2b03ee264a8f95bbaa1500ff0a087"
 dependencies = [
  "euclid 0.19.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.6.18 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -5474,7 +5474,7 @@ dependencies = [
 [[package]]
 name = "webxr-api"
 version = "0.0.1"
-source = "git+https://github.com/servo/webxr#5c0eb61f8f38429fde45673d0884f947d14e9c79"
+source = "git+https://github.com/servo/webxr#b5a4b93fcfb2b03ee264a8f95bbaa1500ff0a087"
 dependencies = [
  "euclid 0.19.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "gleam 0.6.18 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/components/atoms/static_atoms.txt b/components/atoms/static_atoms.txt
index c85d3563e75..7b3d2fc7f88 100644
--- a/components/atoms/static_atoms.txt
+++ b/components/atoms/static_atoms.txt
@@ -25,6 +25,7 @@ dir
 durationchange
 email
 emptied
+end
 ended
 error
 fantasy
diff --git a/components/script/dom/fakexrdevice.rs b/components/script/dom/fakexrdevice.rs
index c1268d743d9..c5e1d16eaff 100644
--- a/components/script/dom/fakexrdevice.rs
+++ b/components/script/dom/fakexrdevice.rs
@@ -38,6 +38,10 @@ impl FakeXRDevice {
             FakeXRDeviceBinding::Wrap,
         )
     }
+
+    pub fn disconnect(&self, sender: IpcSender<()>) {
+        let _ = self.sender.send(MockDeviceMsg::Disconnect(sender));
+    }
 }
 
 pub fn get_views(views: &[FakeXRViewInit]) -> Fallible<Views> {
diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index 7ddc96472ad..ff36a485529 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -547,12 +547,12 @@ pub mod xmlserializer;
 pub mod xr;
 pub mod xrframe;
 pub mod xrinputsource;
-pub mod xrlayer;
 pub mod xrpose;
 pub mod xrreferencespace;
 pub mod xrrenderstate;
 pub mod xrrigidtransform;
 pub mod xrsession;
+pub mod xrsessionevent;
 pub mod xrspace;
 pub mod xrtest;
 pub mod xrview;
diff --git a/components/script/dom/webidls/XRLayer.webidl b/components/script/dom/webidls/XRLayer.webidl
deleted file mode 100644
index 69c65da6143..00000000000
--- a/components/script/dom/webidls/XRLayer.webidl
+++ /dev/null
@@ -1,8 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
-
-// https://immersive-web.github.io/webxr/#xrlayer-interface
-
-[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
-interface XRLayer {};
diff --git a/components/script/dom/webidls/XRRenderState.webidl b/components/script/dom/webidls/XRRenderState.webidl
index 195d5acf3ac..01d7fd39191 100644
--- a/components/script/dom/webidls/XRRenderState.webidl
+++ b/components/script/dom/webidls/XRRenderState.webidl
@@ -7,11 +7,11 @@
 dictionary XRRenderStateInit {
   double depthNear;
   double depthFar;
-  XRLayer baseLayer;
+  XRWebGLLayer baseLayer;
 };
 
 [SecureContext, Exposed=Window, Pref="dom.webxr.enabled"] interface XRRenderState {
   readonly attribute double depthNear;
   readonly attribute double depthFar;
-  readonly attribute XRLayer? baseLayer;
+  readonly attribute XRWebGLLayer? baseLayer;
 };
diff --git a/components/script/dom/webidls/XRSession.webidl b/components/script/dom/webidls/XRSession.webidl
index 1429579353b..6d946ccef55 100644
--- a/components/script/dom/webidls/XRSession.webidl
+++ b/components/script/dom/webidls/XRSession.webidl
@@ -29,7 +29,7 @@ interface XRSession : EventTarget {
   // FrozenArray<XRInputSource> getInputSources();
   sequence<XRInputSource> getInputSources();
 
-  void updateRenderState(optional XRRenderStateInit state = {});
+  [Throws] void updateRenderState(optional XRRenderStateInit state = {});
   long requestAnimationFrame(XRFrameRequestCallback callback);
   void cancelAnimationFrame(long handle);
 
@@ -38,7 +38,7 @@ interface XRSession : EventTarget {
   // // Events
   // attribute EventHandler onblur;
   // attribute EventHandler onfocus;
-  // attribute EventHandler onend;
+  attribute EventHandler onend;
   // attribute EventHandler onselect;
   // attribute EventHandler oninputsourceschange;
   // attribute EventHandler onselectstart;
diff --git a/components/script/dom/webidls/XRSessionEvent.webidl b/components/script/dom/webidls/XRSessionEvent.webidl
new file mode 100644
index 00000000000..f48fa5eb342
--- /dev/null
+++ b/components/script/dom/webidls/XRSessionEvent.webidl
@@ -0,0 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+// https://immersive-web.github.io/webxr/#xrsessionevent-interface
+
+[SecureContext, Exposed=Window, Pref="dom.webxr.enabled", Constructor
+(DOMString type, XRSessionEventInit eventInitDict)]
+interface XRSessionEvent : Event {
+  [SameObject] readonly attribute XRSession session;
+};
+
+dictionary XRSessionEventInit : EventInit {
+  required XRSession session;
+};
diff --git a/components/script/dom/webidls/XRWebGLLayer.webidl b/components/script/dom/webidls/XRWebGLLayer.webidl
index f83e1e4c35a..769b3e9b567 100644
--- a/components/script/dom/webidls/XRWebGLLayer.webidl
+++ b/components/script/dom/webidls/XRWebGLLayer.webidl
@@ -21,7 +21,7 @@ dictionary XRWebGLLayerInit {
             XRWebGLRenderingContext context,
             optional XRWebGLLayerInit layerInit = {}),
     Pref="dom.webxr.enabled"]
-interface XRWebGLLayer : XRLayer {
+interface XRWebGLLayer {
   // // Attributes
   readonly attribute XRWebGLRenderingContext context;
 
diff --git a/components/script/dom/xr.rs b/components/script/dom/xr.rs
index 1ddf93c7a23..d24e8f144cd 100644
--- a/components/script/dom/xr.rs
+++ b/components/script/dom/xr.rs
@@ -76,6 +76,17 @@ impl XR {
         self.pending_immersive_session.set(false);
         self.active_immersive_session.set(Some(session))
     }
+
+    /// https://immersive-web.github.io/webxr/#ref-for-eventdef-xrsession-end
+    pub fn end_session(&self, session: &XRSession) {
+        // Step 3
+        if let Some(active) = self.active_immersive_session.get() {
+            if Dom::from_ref(&*active) == Dom::from_ref(session) {
+                self.active_immersive_session.set(None);
+            }
+        }
+        // XXXManishearth when we support inline sessions we should remove them too
+    }
 }
 
 impl Drop for XR {
diff --git a/components/script/dom/xrlayer.rs b/components/script/dom/xrlayer.rs
deleted file mode 100644
index d17704be28f..00000000000
--- a/components/script/dom/xrlayer.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
-
-use crate::dom::bindings::reflector::Reflector;
-use dom_struct::dom_struct;
-
-#[dom_struct]
-pub struct XRLayer {
-    reflector_: Reflector,
-}
-
-impl XRLayer {
-    pub fn new_inherited() -> XRLayer {
-        XRLayer {
-            reflector_: Reflector::new(),
-        }
-    }
-}
diff --git a/components/script/dom/xrrenderstate.rs b/components/script/dom/xrrenderstate.rs
index 824b7a6d37a..2aba4e46493 100644
--- a/components/script/dom/xrrenderstate.rs
+++ b/components/script/dom/xrrenderstate.rs
@@ -7,7 +7,7 @@ use crate::dom::bindings::num::Finite;
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
 use crate::dom::bindings::root::{DomRoot, MutNullableDom};
 use crate::dom::globalscope::GlobalScope;
-use crate::dom::xrlayer::XRLayer;
+use crate::dom::xrwebgllayer::XRWebGLLayer;
 
 use dom_struct::dom_struct;
 use std::cell::Cell;
@@ -17,14 +17,14 @@ pub struct XRRenderState {
     reflector_: Reflector,
     depth_near: Cell<f64>,
     depth_far: Cell<f64>,
-    layer: MutNullableDom<XRLayer>,
+    layer: MutNullableDom<XRWebGLLayer>,
 }
 
 impl XRRenderState {
     pub fn new_inherited(
         depth_near: f64,
         depth_far: f64,
-        layer: Option<&XRLayer>,
+        layer: Option<&XRWebGLLayer>,
     ) -> XRRenderState {
         XRRenderState {
             reflector_: Reflector::new(),
@@ -38,7 +38,7 @@ impl XRRenderState {
         global: &GlobalScope,
         depth_near: f64,
         depth_far: f64,
-        layer: Option<&XRLayer>,
+        layer: Option<&XRWebGLLayer>,
     ) -> DomRoot<XRRenderState> {
         reflect_dom_object(
             Box::new(XRRenderState::new_inherited(depth_near, depth_far, layer)),
@@ -62,7 +62,7 @@ impl XRRenderState {
     pub fn set_depth_far(&self, depth: f64) {
         self.depth_far.set(depth)
     }
-    pub fn set_layer(&self, layer: Option<&XRLayer>) {
+    pub fn set_layer(&self, layer: Option<&XRWebGLLayer>) {
         self.layer.set(layer)
     }
 }
@@ -79,7 +79,7 @@ impl XRRenderStateMethods for XRRenderState {
     }
 
     /// https://immersive-web.github.io/webxr/#dom-xrrenderstate-baselayer
-    fn GetBaseLayer(&self) -> Option<DomRoot<XRLayer>> {
+    fn GetBaseLayer(&self) -> Option<DomRoot<XRWebGLLayer>> {
         self.layer.get()
     }
 }
diff --git a/components/script/dom/xrsession.rs b/components/script/dom/xrsession.rs
index 50e89a773dc..0ea8a0e0e46 100644
--- a/components/script/dom/xrsession.rs
+++ b/components/script/dom/xrsession.rs
@@ -5,7 +5,9 @@
 use crate::compartments::InCompartment;
 use crate::dom::bindings::callback::ExceptionHandling;
 use crate::dom::bindings::cell::DomRefCell;
+use crate::dom::bindings::codegen::Bindings::NavigatorBinding::NavigatorBinding::NavigatorMethods;
 use crate::dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLRenderingContextMethods;
+use crate::dom::bindings::codegen::Bindings::WindowBinding::WindowBinding::WindowMethods;
 use crate::dom::bindings::codegen::Bindings::XRBinding::XRSessionMode;
 use crate::dom::bindings::codegen::Bindings::XRReferenceSpaceBinding::XRReferenceSpaceType;
 use crate::dom::bindings::codegen::Bindings::XRRenderStateBinding::XRRenderStateInit;
@@ -15,12 +17,13 @@ use crate::dom::bindings::codegen::Bindings::XRSessionBinding::XREnvironmentBlen
 use crate::dom::bindings::codegen::Bindings::XRSessionBinding::XRFrameRequestCallback;
 use crate::dom::bindings::codegen::Bindings::XRSessionBinding::XRSessionMethods;
 use crate::dom::bindings::codegen::Bindings::XRWebGLLayerBinding::XRWebGLLayerMethods;
-use crate::dom::bindings::error::Error;
+use crate::dom::bindings::error::{Error, ErrorResult};
 use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::num::Finite;
 use crate::dom::bindings::refcounted::Trusted;
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
 use crate::dom::bindings::root::{Dom, DomRoot, MutDom, MutNullableDom};
+use crate::dom::event::Event;
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::node::Node;
@@ -28,9 +31,9 @@ use crate::dom::node::NodeDamage;
 use crate::dom::promise::Promise;
 use crate::dom::xrframe::XRFrame;
 use crate::dom::xrinputsource::XRInputSource;
-use crate::dom::xrlayer::XRLayer;
 use crate::dom::xrreferencespace::XRReferenceSpace;
 use crate::dom::xrrenderstate::XRRenderState;
+use crate::dom::xrsessionevent::XRSessionEvent;
 use crate::dom::xrspace::XRSpace;
 use crate::dom::xrwebgllayer::XRWebGLLayer;
 use crate::task_source::TaskSource;
@@ -42,12 +45,12 @@ use profile_traits::ipc;
 use std::cell::Cell;
 use std::mem;
 use std::rc::Rc;
-use webxr_api::{self, Frame, Session};
+use webxr_api::{self, Event as XREvent, Frame, Session};
 
 #[dom_struct]
 pub struct XRSession {
     eventtarget: EventTarget,
-    base_layer: MutNullableDom<XRLayer>,
+    base_layer: MutNullableDom<XRWebGLLayer>,
     blend_mode: XREnvironmentBlendMode,
     viewer_space: MutNullableDom<XRSpace>,
     #[ignore_malloc_size_of = "defined in webxr"]
@@ -62,6 +65,11 @@ pub struct XRSession {
     #[ignore_malloc_size_of = "defined in ipc-channel"]
     raf_sender: DomRefCell<Option<IpcSender<(f64, Frame)>>>,
     input_sources: DomRefCell<Vec<Dom<XRInputSource>>>,
+    // Any promises from calling end()
+    #[ignore_malloc_size_of = "promises are hard"]
+    end_promises: DomRefCell<Vec<Rc<Promise>>>,
+    /// https://immersive-web.github.io/webxr/#ended
+    ended: Cell<bool>,
 }
 
 impl XRSession {
@@ -81,6 +89,8 @@ impl XRSession {
             raf_callback_list: DomRefCell::new(vec![]),
             raf_sender: DomRefCell::new(None),
             input_sources: DomRefCell::new(vec![]),
+            end_promises: DomRefCell::new(vec![]),
+            ended: Cell::new(false),
         }
     }
 
@@ -100,6 +110,7 @@ impl XRSession {
                 input_sources.push(Dom::from_ref(&input));
             }
         }
+        ret.attach_event_handler();
         ret
     }
 
@@ -108,6 +119,71 @@ impl XRSession {
         with(&session)
     }
 
+    pub fn is_ended(&self) -> bool {
+        self.ended.get()
+    }
+
+    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();
+        let (task_source, canceller) = window
+            .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| {
+                let this = this.clone();
+                let _ = task_source.queue_with_canceller(
+                    task!(xr_event_callback: move || {
+                        this.root().event_callback(message.to().unwrap());
+                    }),
+                    &canceller,
+                );
+            }),
+        );
+
+        // request animation frame
+        self.session
+            .borrow_mut()
+            .set_event_callback(EventCallback { sender });
+    }
+
+    fn event_callback(&self, event: XREvent) {
+        match event {
+            XREvent::SessionEnd => {
+                // https://immersive-web.github.io/webxr/#shut-down-the-session
+                // Step 2
+                self.ended.set(true);
+                // Step 3-4
+                self.global().as_window().Navigator().Xr().end_session(self);
+                // Step 5: We currently do not have any such promises
+                // Step 6 is happening n the XR session
+                // https://immersive-web.github.io/webxr/#dom-xrsession-end step 3
+                for promise in self.end_promises.borrow_mut().drain(..) {
+                    promise.resolve_native(&());
+                }
+                // Step 7
+                let event = XRSessionEvent::new(&self.global(), atom!("end"), false, false, self);
+                event.upcast::<Event>().fire(self.upcast());
+            },
+            _ => (), // XXXManishearth TBD
+        }
+    }
+
     /// https://immersive-web.github.io/webxr/#xr-animation-frame
     fn raf_callback(&self, (time, frame): (f64, Frame)) {
         // Step 1
@@ -122,13 +198,9 @@ impl XRSession {
             let layer = pending.GetBaseLayer();
             if let Some(layer) = layer {
                 let mut session = self.session.borrow_mut();
-                if let Some(layer) = layer.downcast::<XRWebGLLayer>() {
-                    session.update_webgl_external_image_api(
-                        layer.Context().webgl_sender().webxr_external_image_api(),
-                    );
-                } else {
-                    error!("updateRenderState() called with unknown layer type")
-                }
+                session.update_webgl_external_image_api(
+                    layer.Context().webgl_sender().webxr_external_image_api(),
+                );
             }
         }
 
@@ -160,17 +232,18 @@ impl XRSession {
 
         // If the canvas element is attached to the DOM, it is now dirty,
         // and we need to trigger a reflow.
-        if let Some(webgl_layer) = base_layer.downcast::<XRWebGLLayer>() {
-            webgl_layer
-                .Context()
-                .Canvas()
-                .upcast::<Node>()
-                .dirty(NodeDamage::OtherNodeDamage);
-        }
+        base_layer
+            .Context()
+            .Canvas()
+            .upcast::<Node>()
+            .dirty(NodeDamage::OtherNodeDamage);
     }
 }
 
 impl XRSessionMethods for XRSession {
+    /// https://immersive-web.github.io/webxr/#eventdef-xrsession-end
+    event_handler!(end, GetOnend, SetOnend);
+
     /// https://immersive-web.github.io/webxr/#dom-xrsession-mode
     fn Mode(&self) -> XRSessionMode {
         XRSessionMode::Immersive_vr
@@ -182,11 +255,19 @@ impl XRSessionMethods for XRSession {
     }
 
     /// https://immersive-web.github.io/webxr/#dom-xrsession-updaterenderstate
-    fn UpdateRenderState(&self, init: &XRRenderStateInit, _: InCompartment) {
-        // XXXManishearth various checks:
-        // If session’s ended value is true, throw an InvalidStateError and abort these steps
-        // If newState’s baseLayer's was created with an XRSession other than session,
-        // throw an InvalidStateError and abort these steps
+    fn UpdateRenderState(&self, init: &XRRenderStateInit, _: InCompartment) -> ErrorResult {
+        // Step 2
+        if self.ended.get() {
+            return Err(Error::InvalidState);
+        }
+        // Step 3:
+        if let Some(ref layer) = init.baseLayer {
+            if Dom::from_ref(layer.session()) != Dom::from_ref(self) {
+                return Err(Error::InvalidState);
+            }
+        }
+
+        // XXXManishearth step 4:
         // If newState’s inlineVerticalFieldOfView is set and session is an
         // immersive session, throw an InvalidStateError and abort these steps.
 
@@ -203,6 +284,7 @@ impl XRSessionMethods for XRSession {
             pending.set_layer(Some(&layer))
         }
         // XXXManishearth handle inlineVerticalFieldOfView
+        Ok(())
     }
 
     /// https://immersive-web.github.io/webxr/#dom-xrsession-requestanimationframe
@@ -305,9 +387,15 @@ impl XRSessionMethods for XRSession {
 
     /// https://immersive-web.github.io/webxr/#dom-xrsession-end
     fn End(&self) -> Rc<Promise> {
-        // XXXManishearth implement device disconnection and session ending
-        let p = Promise::new(&self.global());
-        p.resolve_native(&());
+        let global = self.global();
+        let p = Promise::new(&global);
+        self.end_promises.borrow_mut().push(p.clone());
+        // This is duplicated in event_callback since this should
+        // happen ASAP for end() but can happen later if the device
+        // shuts itself down
+        self.ended.set(true);
+        global.as_window().Navigator().Xr().end_session(self);
+        self.session.borrow_mut().end_session();
         p
     }
 }
diff --git a/components/script/dom/xrsessionevent.rs b/components/script/dom/xrsessionevent.rs
new file mode 100644
index 00000000000..6c2e8c0fb00
--- /dev/null
+++ b/components/script/dom/xrsessionevent.rs
@@ -0,0 +1,78 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use crate::dom::bindings::codegen::Bindings::EventBinding::EventBinding::EventMethods;
+use crate::dom::bindings::codegen::Bindings::XRSessionEventBinding::{self, XRSessionEventMethods};
+use crate::dom::bindings::error::Fallible;
+use crate::dom::bindings::inheritance::Castable;
+use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::bindings::str::DOMString;
+use crate::dom::event::Event;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::window::Window;
+use crate::dom::xrsession::XRSession;
+use dom_struct::dom_struct;
+use servo_atoms::Atom;
+
+#[dom_struct]
+pub struct XRSessionEvent {
+    event: Event,
+    session: Dom<XRSession>,
+}
+
+impl XRSessionEvent {
+    #[allow(unrooted_must_root)]
+    fn new_inherited(session: &XRSession) -> XRSessionEvent {
+        XRSessionEvent {
+            event: Event::new_inherited(),
+            session: Dom::from_ref(session),
+        }
+    }
+
+    pub fn new(
+        global: &GlobalScope,
+        type_: Atom,
+        bubbles: bool,
+        cancelable: bool,
+        session: &XRSession,
+    ) -> DomRoot<XRSessionEvent> {
+        let trackevent = reflect_dom_object(
+            Box::new(XRSessionEvent::new_inherited(&session)),
+            global,
+            XRSessionEventBinding::Wrap,
+        );
+        {
+            let event = trackevent.upcast::<Event>();
+            event.init_event(type_, bubbles, cancelable);
+        }
+        trackevent
+    }
+
+    pub fn Constructor(
+        window: &Window,
+        type_: DOMString,
+        init: &XRSessionEventBinding::XRSessionEventInit,
+    ) -> Fallible<DomRoot<XRSessionEvent>> {
+        Ok(XRSessionEvent::new(
+            &window.global(),
+            Atom::from(type_),
+            init.parent.bubbles,
+            init.parent.cancelable,
+            &init.session,
+        ))
+    }
+}
+
+impl XRSessionEventMethods for XRSessionEvent {
+    // https://immersive-web.github.io/webxr/#dom-xrsessioneventinit-session
+    fn Session(&self) -> DomRoot<XRSession> {
+        DomRoot::from_ref(&*self.session)
+    }
+
+    // https://dom.spec.whatwg.org/#dom-event-istrusted
+    fn IsTrusted(&self) -> bool {
+        self.event.IsTrusted()
+    }
+}
diff --git a/components/script/dom/xrtest.rs b/components/script/dom/xrtest.rs
index 3e695bc1f5e..81949addf02 100644
--- a/components/script/dom/xrtest.rs
+++ b/components/script/dom/xrtest.rs
@@ -7,13 +7,14 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use crate::dom::bindings::callback::ExceptionHandling;
+use crate::dom::bindings::cell::DomRefCell;
 use crate::dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use crate::dom::bindings::codegen::Bindings::XRTestBinding::{
     self, FakeXRDeviceInit, XRTestMethods,
 };
 use crate::dom::bindings::refcounted::{Trusted, TrustedPromise};
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
-use crate::dom::bindings::root::DomRoot;
+use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::fakexrdevice::{get_origin, get_views, FakeXRDevice};
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::promise::Promise;
@@ -31,6 +32,7 @@ use webxr_api::{self, Error as XRError, MockDeviceInit, MockDeviceMsg};
 pub struct XRTest {
     reflector: Reflector,
     session_started: Cell<bool>,
+    devices_connected: DomRefCell<Vec<Dom<FakeXRDevice>>>,
 }
 
 impl XRTest {
@@ -38,6 +40,7 @@ impl XRTest {
         XRTest {
             reflector: Reflector::new(),
             session_started: Cell::new(false),
+            devices_connected: DomRefCell::new(vec![]),
         }
     }
 
@@ -57,6 +60,9 @@ impl XRTest {
         let promise = trusted.root();
         if let Ok(sender) = response {
             let device = FakeXRDevice::new(&self.global(), sender);
+            self.devices_connected
+                .borrow_mut()
+                .push(Dom::from_ref(&device));
             promise.resolve_native(&device);
         } else {
             promise.reject_native(&());
@@ -174,8 +180,45 @@ impl XRTestMethods for XRTest {
     /// https://github.com/immersive-web/webxr-test-api/blob/master/explainer.md
     fn DisconnectAllDevices(&self) -> Rc<Promise> {
         // XXXManishearth implement device disconnection and session ending
-        let p = Promise::new(&self.global());
-        p.resolve_native(&());
+        let global = self.global();
+        let p = Promise::new(&global);
+        let mut devices = self.devices_connected.borrow_mut();
+        if devices.is_empty() {
+            p.resolve_native(&());
+        } else {
+            let mut len = devices.len();
+
+            let (sender, receiver) = ipc::channel(global.time_profiler_chan().clone()).unwrap();
+            let mut rooted_devices: Vec<_> =
+                devices.iter().map(|x| DomRoot::from_ref(&**x)).collect();
+            devices.clear();
+            for device in rooted_devices.drain(..) {
+                device.disconnect(sender.clone());
+            }
+            let mut trusted = Some(TrustedPromise::new(p.clone()));
+            let (task_source, canceller) = global
+                .as_window()
+                .task_manager()
+                .dom_manipulation_task_source_with_canceller();
+
+            ROUTER.add_route(
+                receiver.to_opaque(),
+                Box::new(move |_| {
+                    len -= 1;
+                    if len == 0 {
+                        let trusted = trusted
+                            .take()
+                            .expect("DisconnectAllDevices disconnected more devices than expected");
+                        let _ =
+                            task_source.queue_with_canceller(trusted.resolve_task(()), &canceller);
+                    }
+                }),
+            );
+
+            // XXXManishearth this is a hack, it will need to be replaced when
+            // we improve how mock messaging works
+            p.resolve_native(&())
+        };
         p
     }
 }
diff --git a/components/script/dom/xrwebgllayer.rs b/components/script/dom/xrwebgllayer.rs
index a2a7c93f37c..a5f06df0e52 100644
--- a/components/script/dom/xrwebgllayer.rs
+++ b/components/script/dom/xrwebgllayer.rs
@@ -10,14 +10,13 @@ use crate::dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGL
 use crate::dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLRenderingContextConstants as constants;
 use crate::dom::bindings::error::Error;
 use crate::dom::bindings::error::Fallible;
-use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
+use crate::dom::bindings::reflector::{reflect_dom_object, Reflector, DomObject};
 use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::webgl_validations::types::TexImageTarget;
 use crate::dom::webglframebuffer::WebGLFramebuffer;
 use crate::dom::webglrenderingcontext::WebGLRenderingContext;
 use crate::dom::window::Window;
-use crate::dom::xrlayer::XRLayer;
 use crate::dom::xrsession::XRSession;
 use crate::dom::xrview::XRView;
 use crate::dom::xrviewport::XRViewport;
@@ -28,7 +27,7 @@ use webxr_api::Views;
 
 #[dom_struct]
 pub struct XRWebGLLayer {
-    xrlayer: XRLayer,
+    reflector_: Reflector,
     antialias: bool,
     depth: bool,
     stencil: bool,
@@ -46,7 +45,7 @@ impl XRWebGLLayer {
         framebuffer: &WebGLFramebuffer,
     ) -> XRWebGLLayer {
         XRWebGLLayer {
-            xrlayer: XRLayer::new_inherited(),
+            reflector_: Reflector::new(),
             antialias: init.antialias,
             depth: init.depth,
             stencil: init.stencil,
@@ -83,6 +82,13 @@ impl XRWebGLLayer {
         context: &WebGLRenderingContext,
         init: &XRWebGLLayerInit,
     ) -> Fallible<DomRoot<Self>> {
+        // Step 2
+        if session.is_ended() {
+            return Err(Error::InvalidState);
+        }
+        // XXXManishearth step 3: throw error if context is lost
+        // XXXManishearth step 4: check XR compat flag for immersive sessions
+
         let cx = global.get_cx();
         let old_fbo = context.bound_framebuffer();
         let old_texture = context
@@ -139,6 +145,10 @@ impl XRWebGLLayer {
             &framebuffer,
         ))
     }
+
+    pub fn session(&self) -> &XRSession {
+        &self.session
+    }
 }
 
 impl XRWebGLLayerMethods for XRWebGLLayer {
diff --git a/tests/wpt/metadata/webxr/idlharness.https.window.js.ini b/tests/wpt/metadata/webxr/idlharness.https.window.js.ini
index b3906bc63f5..c85b29a6c1d 100644
--- a/tests/wpt/metadata/webxr/idlharness.https.window.js.ini
+++ b/tests/wpt/metadata/webxr/idlharness.https.window.js.ini
@@ -44,18 +44,12 @@
   [XRInputSourceArray interface: attribute length]
     expected: FAIL
 
-  [XRSessionEvent interface: existence and properties of interface object]
-    expected: FAIL
-
   [XRInputSource interface: attribute targetRayMode]
     expected: FAIL
 
   [XRBoundedReferenceSpace interface object length]
     expected: FAIL
 
-  [XRSessionEvent interface object length]
-    expected: FAIL
-
   [XRWebGLLayer interface: operation getNativeFramebufferScaleFactor(XRSession)]
     expected: FAIL
 
@@ -74,18 +68,12 @@
   [XRReferenceSpaceEvent interface object length]
     expected: FAIL
 
-  [XRSessionEvent interface: existence and properties of interface prototype object's @@unscopables property]
-    expected: FAIL
-
   [WebGLRenderingContext interface: operation makeXRCompatible()]
     expected: FAIL
 
   [XRInputSourcesChangeEvent interface: attribute added]
     expected: FAIL
 
-  [XRSessionEvent interface object name]
-    expected: FAIL
-
   [XRInputSourceEvent interface: attribute inputSource]
     expected: FAIL
 
@@ -98,18 +86,12 @@
   [XRInputSourcesChangeEvent interface: attribute removed]
     expected: FAIL
 
-  [XRSessionEvent interface: existence and properties of interface prototype object's "constructor" property]
-    expected: FAIL
-
   [XRSession interface: attribute onselectstart]
     expected: FAIL
 
   [XRInputSourceEvent interface: existence and properties of interface prototype object]
     expected: FAIL
 
-  [XRSessionEvent interface: attribute session]
-    expected: FAIL
-
   [XRReferenceSpaceEvent interface: existence and properties of interface object]
     expected: FAIL
 
@@ -149,12 +131,6 @@
   [XRBoundedReferenceSpace interface: attribute boundsGeometry]
     expected: FAIL
 
-  [XRWebGLLayer interface: existence and properties of interface object]
-    expected: FAIL
-
-  [XRWebGLLayer interface: existence and properties of interface prototype object]
-    expected: FAIL
-
   [XRReferenceSpaceEvent interface object name]
     expected: FAIL
 
@@ -236,18 +212,12 @@
   [XRSession interface: attribute oninputsourceschange]
     expected: FAIL
 
-  [XRSessionEvent interface: existence and properties of interface prototype object]
-    expected: FAIL
-
   [XRBoundedReferenceSpace interface: existence and properties of interface prototype object]
     expected: FAIL
 
   [XR interface: calling requestSession(XRSessionMode, XRSessionInit) on navigator.xr with too few arguments must throw TypeError]
     expected: FAIL
 
-  [XRSession interface: attribute onend]
-    expected: FAIL
-
   [XRSession interface: operation end()]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/webxr/xrSession_end.https.html.ini b/tests/wpt/metadata/webxr/xrSession_end.https.html.ini
index 99ff6da253a..d03914bcd66 100644
--- a/tests/wpt/metadata/webxr/xrSession_end.https.html.ini
+++ b/tests/wpt/metadata/webxr/xrSession_end.https.html.ini
@@ -1,8 +1,5 @@
 [xrSession_end.https.html]
-  expected: TIMEOUT
+  expected: ERROR
   [end event fires when non-immersive session ends]
     expected: NOTRUN
 
-  [end event fires when immersive session ends]
-    expected: TIMEOUT
-
diff --git a/tests/wpt/metadata/webxr/xrSession_input_events_end.https.html.ini b/tests/wpt/metadata/webxr/xrSession_input_events_end.https.html.ini
index 739e7b4c112..fba510c47e9 100644
--- a/tests/wpt/metadata/webxr/xrSession_input_events_end.https.html.ini
+++ b/tests/wpt/metadata/webxr/xrSession_input_events_end.https.html.ini
@@ -1,4 +1,5 @@
 [xrSession_input_events_end.https.html]
+  expected: ERROR
   [Calling end during an input callback stops processing at the right time]
     expected: FAIL