Auto merge of #23253 - BartGitHub:refactor-promise-compartment, r=jdm

Refactor promise compartment

<!-- Please describe your changes on the following line: -->
This PR adds a mechanism to verify that certain code is executed inside a ```JSAutoCompartment```, and applies this to the ```Promise::new_in_current_compartment``` constructor.

r? @jdm

---
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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 #23167

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- [x] These changes do not require tests because they do not change existing functionality.

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1 files changed, 11 insertions, 4 deletions

diff --git a/components/script/dom/testbinding.rs b/components/script/dom/testbinding.rs
index f5d64a478de..99e294e75e9 100644
--- a/components/script/dom/testbinding.rs
+++ b/components/script/dom/testbinding.rs
@@ -4,6 +4,7 @@
 
 // check-tidy: no specs after this line
 
+use crate::compartments::{AlreadyInCompartment, InCompartment};
 use crate::dom::bindings::callback::ExceptionHandling;
 use crate::dom::bindings::codegen::Bindings::EventListenerBinding::EventListener;
 use crate::dom::bindings::codegen::Bindings::FunctionBinding::Function;
@@ -1009,7 +1010,6 @@ impl TestBindingMethods for TestBinding {
         );
     }
 
-    #[allow(unsafe_code)]
     fn PromiseNativeHandler(
         &self,
         resolve: Option<Rc<SimpleCallback>>,
@@ -1021,7 +1021,11 @@ impl TestBindingMethods for TestBinding {
             resolve.map(SimpleHandler::new),
             reject.map(SimpleHandler::new),
         );
-        let p = unsafe { Promise::new_in_current_compartment(&global) };
+        let in_compartment_proof = AlreadyInCompartment::assert(&global);
+        let p = Promise::new_in_current_compartment(
+            &global,
+            InCompartment::Already(&in_compartment_proof),
+        );
         p.append_native_handler(&handler);
         return p;
 
@@ -1044,9 +1048,12 @@ impl TestBindingMethods for TestBinding {
         }
     }
 
-    #[allow(unsafe_code)]
     fn PromiseAttribute(&self) -> Rc<Promise> {
-        unsafe { Promise::new_in_current_compartment(&self.global()) }
+        let in_compartment_proof = AlreadyInCompartment::assert(&self.global());
+        Promise::new_in_current_compartment(
+            &self.global(),
+            InCompartment::Already(&in_compartment_proof),
+        )
     }
 
     fn AcceptPromise(&self, _promise: &Promise) {}