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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components/script/dom/document.rs

@@ -2,6 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+use crate::compartments::{AlreadyInCompartment, InCompartment};
 use crate::document_loader::{DocumentLoader, LoadType};
 use crate::dom::activation::{synthetic_click_activation, ActivationSource};
 use crate::dom::attr::Attr;
@@ -2988,10 +2989,13 @@ impl Document {
     }
 
     // https://fullscreen.spec.whatwg.org/#dom-element-requestfullscreen
-    #[allow(unsafe_code)]
     pub fn enter_fullscreen(&self, pending: &Element) -> Rc<Promise> {
         // Step 1
-        let promise = unsafe { Promise::new_in_current_compartment(&self.global()) };
+        let in_compartment_proof = AlreadyInCompartment::assert(&self.global());
+        let promise = Promise::new_in_current_compartment(
+            &self.global(),
+            InCompartment::Already(&in_compartment_proof),
+        );
         let mut error = false;
 
         // Step 4
@@ -3055,11 +3059,14 @@ impl Document {
     }
 
     // https://fullscreen.spec.whatwg.org/#exit-fullscreen
-    #[allow(unsafe_code)]
     pub fn exit_fullscreen(&self) -> Rc<Promise> {
         let global = self.global();
         // Step 1
-        let promise = unsafe { Promise::new_in_current_compartment(&global) };
+        let in_compartment_proof = AlreadyInCompartment::assert(&global);
+        let promise = Promise::new_in_current_compartment(
+            &global,
+            InCompartment::Already(&in_compartment_proof),
+        );
         // Step 2
         if self.fullscreen_element.get().is_none() {
             promise.reject_error(Error::Type(String::from("fullscreen is null")));