Auto merge of #22953 - asajeffrey:webvr-glwindow, r=paulrouget

Use a test VRDisplay that renders to a GL window

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Add a `dom.webvr.test` pref that registers a new VR display, which registers to a GL window.

The matching webvr PR is https://github.com/servo/rust-webvr/pull/66.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #22795
- [X] These changes do not require tests because we need a followup PR to support reftests which use the VR display

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1 files changed, 2 insertions, 0 deletions

diff --git a/components/compositing/compositor_thread.rs b/components/compositing/compositor_thread.rs
index e4dee4f595a..1a7ee9309cb 100644
--- a/components/compositing/compositor_thread.rs
+++ b/components/compositing/compositor_thread.rs
@@ -18,6 +18,7 @@ use script_traits::{AnimationState, ConstellationMsg, EventResult};
 use std::fmt::{Debug, Error, Formatter};
 use style_traits::viewport::ViewportConstraints;
 use webrender_api::{self, DeviceIntPoint, DeviceIntSize};
+use webvr_traits::WebVRMainThreadHeartbeat;
 
 /// Sends messages to the compositor.
 pub struct CompositorProxy {
@@ -153,4 +154,5 @@ pub struct InitialCompositorState {
     pub webrender: webrender::Renderer,
     pub webrender_document: webrender_api::DocumentId,
     pub webrender_api: webrender_api::RenderApi,
+    pub webvr_heartbeats: Vec<Box<WebVRMainThreadHeartbeat>>,
 }