Auto merge of #24862 - jdm:js-init-destroy-fit-the-second, r=asajeffrey

Ensure SpiderMonkey shuts down cleanly

This is the alternate solution that I described in #24845. Given how much simpler the resulting code is, I'm now much more in favour of this design. Depends on https://github.com/servo/rust-mozjs/pull/487.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #21696 and fix #22276
- [x] There are tests for these changes

1 files changed, 4 insertions, 1 deletions

diff --git a/components/script/init.rs b/components/script/init.rs
index 15428f4f3fe..30e01dda74e 100644
--- a/components/script/init.rs
+++ b/components/script/init.rs
@@ -4,6 +4,7 @@
 
 use crate::dom::bindings::codegen::RegisterBindings;
 use crate::dom::bindings::proxyhandler;
+use crate::script_runtime::JSEngineSetup;
 use crate::serviceworker_manager::ServiceWorkerManager;
 use script_traits::SWManagerSenders;
 
@@ -56,7 +57,7 @@ pub fn init_service_workers(sw_senders: SWManagerSenders) {
 }
 
 #[allow(unsafe_code)]
-pub fn init() {
+pub fn init() -> JSEngineSetup {
     unsafe {
         proxyhandler::init();
 
@@ -66,4 +67,6 @@ pub fn init() {
     }
 
     perform_platform_specific_initialization();
+
+    JSEngineSetup::new()
 }