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, 32 insertions, 0 deletions

diff --git a/components/script/dom/xrreferencespace.rs b/components/script/dom/xrreferencespace.rs
new file mode 100644
index 00000000000..308b710d928
--- /dev/null
+++ b/components/script/dom/xrreferencespace.rs
@@ -0,0 +1,32 @@
+/* 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::XRReferenceSpaceBinding;
+use crate::dom::bindings::reflector::reflect_dom_object;
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::xrspace::XRSpace;
+use dom_struct::dom_struct;
+
+#[dom_struct]
+pub struct XRReferenceSpace {
+    xrspace: XRSpace,
+}
+
+impl XRReferenceSpace {
+    pub fn new_inherited() -> XRReferenceSpace {
+        XRReferenceSpace {
+            xrspace: XRSpace::new_inherited(),
+        }
+    }
+
+    #[allow(unused)]
+    pub fn new(global: &GlobalScope) -> DomRoot<XRReferenceSpace> {
+        reflect_dom_object(
+            Box::new(XRReferenceSpace::new_inherited()),
+            global,
+            XRReferenceSpaceBinding::Wrap,
+        )
+    }
+}