LibJS: Add ScriptOrModule to execution context and track it everywhere

Author: https://github.com/davidot
Commit: 57c5a59cab
Pull-request: https://github.com/SerenityOS/serenity/pull/11957
Reviewed-by: https://github.com/emanuele6
Reviewed-by: https://github.com/linusg

Userland/Libraries/LibJS/Runtime/ShadowRealmConstructor.cpp

@@ -55,7 +55,7 @@ ThrowCompletionOr<Object*> ShadowRealmConstructor::construct(FunctionObject& new
     context.realm = realm;
 
     // 8. Set the ScriptOrModule of context to null.
-    // FIXME: Our execution context struct currently does not track this item.
+    // Note: This is already the default value.
 
     // 2. Let O be ? OrdinaryCreateFromConstructor(NewTarget, "%ShadowRealm.prototype%", « [[ShadowRealm]], [[ExecutionContext]] »).
     // 4. Set O.[[ShadowRealm]] to realmRec.