Auto merge of #22528 - Manishearth:webxr, r=jdm,MortimerGoro

Preliminary WebXR support

This implements just enough WebXR to display to 3DOF devices in
immersive mode only.

Couple missing things:

 - [ ] Handling reference spaces (even if just supporting eye-level spaces)
 - [x] Spec links
 - [ ] We enter immersive mode when baseLayer is set, but it seems like
we're supposed to do this when requestSession is called (https://github.com/immersive-web/webxr/issues/453)
 - [ ] VR/XR should block less (https://github.com/servo/servo/issues/22505)
 - [x] More pref-gating
 - [x] `views` is a method instead of an attribute because we don't support FrozenArray

<s>Once I add spec links and pref gating</s> this can be landed as-is for further experimentation.

r? @jdm @MortimerGoro

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1 files changed, 15 insertions, 10 deletions

diff --git a/components/script/dom/navigator.rs b/components/script/dom/navigator.rs
index 04669ca25d9..aa49701709a 100644
--- a/components/script/dom/navigator.rs
+++ b/components/script/dom/navigator.rs
@@ -4,7 +4,7 @@
 
 use crate::dom::bindings::codegen::Bindings::NavigatorBinding;
 use crate::dom::bindings::codegen::Bindings::NavigatorBinding::NavigatorMethods;
-use crate::dom::bindings::codegen::Bindings::VRBinding::VRBinding::VRMethods;
+use crate::dom::bindings::error::Error;
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
 use crate::dom::bindings::root::{DomRoot, MutNullableDom};
 use crate::dom::bindings::str::DOMString;
@@ -16,8 +16,8 @@ use crate::dom::permissions::Permissions;
 use crate::dom::pluginarray::PluginArray;
 use crate::dom::promise::Promise;
 use crate::dom::serviceworkercontainer::ServiceWorkerContainer;
-use crate::dom::vr::VR;
 use crate::dom::window::Window;
+use crate::dom::xr::XR;
 use dom_struct::dom_struct;
 use std::rc::Rc;
 
@@ -28,7 +28,7 @@ pub struct Navigator {
     plugins: MutNullableDom<PluginArray>,
     mime_types: MutNullableDom<MimeTypeArray>,
     service_worker: MutNullableDom<ServiceWorkerContainer>,
-    vr: MutNullableDom<VR>,
+    xr: MutNullableDom<XR>,
     gamepads: MutNullableDom<GamepadList>,
     permissions: MutNullableDom<Permissions>,
 }
@@ -41,7 +41,7 @@ impl Navigator {
             plugins: Default::default(),
             mime_types: Default::default(),
             service_worker: Default::default(),
-            vr: Default::default(),
+            xr: Default::default(),
             gamepads: Default::default(),
             permissions: Default::default(),
         }
@@ -135,7 +135,7 @@ impl NavigatorMethods for Navigator {
             .gamepads
             .or_init(|| GamepadList::new(&self.global(), &[]));
 
-        let vr_gamepads = self.Vr().get_gamepads();
+        let vr_gamepads = self.Xr().get_gamepads();
         root.add_if_not_exists(&vr_gamepads);
         // TODO: Add not VR related gamepads
         root
@@ -149,12 +149,17 @@ impl NavigatorMethods for Navigator {
     // https://w3c.github.io/webvr/spec/1.1/#navigator-getvrdisplays-attribute
     #[allow(unrooted_must_root)]
     fn GetVRDisplays(&self) -> Rc<Promise> {
-        self.Vr().GetDisplays()
+        let promise = Promise::new(&self.global());
+        let displays = self.Xr().get_displays();
+        match displays {
+            Ok(displays) => promise.resolve_native(&displays),
+            Err(_) => promise.reject_error(Error::Security),
+        }
+        promise
     }
-}
 
-impl Navigator {
-    pub fn Vr(&self) -> DomRoot<VR> {
-        self.vr.or_init(|| VR::new(&self.global()))
+    /// https://immersive-web.github.io/webxr/#dom-navigator-xr
+    fn Xr(&self) -> DomRoot<XR> {
+        self.xr.or_init(|| XR::new(&self.global()))
     }
 }