Auto merge of #23485 - Manishearth:xrtest, r=asajeffrey

Basic XR Testing support

This adds support for the XRTest and FakeXRDeviceController APIs from https://github.com/immersive-web/webxr-test-api, and plugs them into the `mock` backend of rust-webvr.

Tested with [a modified webxr test page](https://github.com/immersive-web/webxr-test-api)

r? @jdm @asajeffrey

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1 files changed, 8 insertions, 0 deletions

diff --git a/components/script/dom/xr.rs b/components/script/dom/xr.rs
index 3ff67b0042c..1626ad4e00e 100644
--- a/components/script/dom/xr.rs
+++ b/components/script/dom/xr.rs
@@ -21,6 +21,7 @@ use crate::dom::promise::Promise;
 use crate::dom::vrdisplay::VRDisplay;
 use crate::dom::vrdisplayevent::VRDisplayEvent;
 use crate::dom::xrsession::XRSession;
+use crate::dom::xrtest::XRTest;
 use dom_struct::dom_struct;
 use ipc_channel::ipc::IpcSender;
 use profile_traits::ipc;
@@ -36,6 +37,7 @@ pub struct XR {
     gamepads: DomRefCell<Vec<Dom<Gamepad>>>,
     pending_immersive_session: Cell<bool>,
     active_immersive_session: MutNullableDom<VRDisplay>,
+    test: MutNullableDom<XRTest>,
 }
 
 impl XR {
@@ -46,6 +48,7 @@ impl XR {
             gamepads: DomRefCell::new(Vec::new()),
             pending_immersive_session: Cell::new(false),
             active_immersive_session: Default::default(),
+            test: Default::default(),
         }
     }
 
@@ -141,6 +144,11 @@ impl XRMethods for XR {
         session.xr_present(promise.clone());
         promise
     }
+
+    // https://github.com/immersive-web/webxr-test-api/blob/master/explainer.md
+    fn Test(&self) -> DomRoot<XRTest> {
+        self.test.or_init(|| XRTest::new(&self.global()))
+    }
 }
 
 impl XR {