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/ShadowRealm.cpp

@@ -93,7 +93,7 @@ ThrowCompletionOr<Value> perform_shadow_realm_eval(GlobalObject& global_object,
     eval_context.realm = &eval_realm;
 
     // 15. Set evalContext's ScriptOrModule to null.
-    // FIXME: Our execution context struct currently does not track this item.
+    // Note: This is already the default value.
 
     // 16. Set evalContext's VariableEnvironment to varEnv.
     eval_context.variable_environment = variable_environment;