Auto merge of #27429 - asajeffrey:webxr-user-intent-pref, r=Manishearth

Add a pref to indicate user intent to enter webxr

<!-- Please describe your changes on the following line: -->

Add a pref to indicate that the user has indicated intent to enter webxr.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because it's a command-line pref

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components/config/prefs.rs

@@ -301,6 +301,8 @@ mod gen {
                         enabled: bool,
                     },
                     sessionavailable: bool,
+                    #[serde(rename = "dom.webxr.unsafe-assume-user-intent")]
+                    unsafe_assume_user_intent: bool,
                 },
                 worklet: {
                     blockingsleep: {

components/script/dom/xrsystem.rs

@@ -162,8 +162,12 @@ impl XRSystemMethods for XRSystem {
 
         if mode != XRSessionMode::Inline {
             if !ScriptThread::is_user_interacting() {
-                promise.reject_error(Error::Security);
+                if pref!(dom.webxr.unsafe_assume_user_intent) {
-                return promise;
+                    warn!("The dom.webxr.unsafe-assume-user-intent preference assumes user intent to enter WebXR.");
+                } else {
+                    promise.reject_error(Error::Security);
+                    return promise;
+                }
             }
 
             if self.pending_or_active_session() {

ports/gstplugin/servowebsrc.rs

@@ -218,6 +218,7 @@ impl ServoThread {
             None => Some(webrender_swap_chain),
             Some(..) => {
                 set_pref!(dom.webxr.sessionavailable, true);
+                set_pref!(dom.webxr.unsafe_assume_user_intent, true);
                 servo.handle_events(vec![WindowEvent::ChangeBrowserVisibility(id, false)]);
                 None
             },

resources/prefs.json

@@ -50,6 +50,7 @@
   "dom.webxr.layers.enabled": false,
   "dom.webxr.sessionavailable": false,
   "dom.webxr.test": false,
+  "dom.webxr.unsafe-assume-user-intent": false,
   "dom.worklet.timeout_ms": 10,
   "gfx.subpixel-text-antialiasing.enabled": true,
   "gfx.texture-swizzling.enabled": true,