Attempt to log the stack where cross-request promises are being resolved

src/workerd/io/worker.c++

@@ -1194,6 +1194,17 @@ Worker::Isolate::Isolate(kj::Own<Api> apiParam,
                   v8::Local<v8::Value> argument)> callback) -> v8::Maybe<void> {
         try {
           auto& js = jsg::Lock::from(isolate);
+
+          // TODO(soon): Hopefully this logging is temporary. We want to get an idea
+          // of where the cross request promises are being resolved just in general.
+          // To do so we need to try to capture a stack. We do so by creating an error
+          // object and logging it.
+          auto err = v8::Exception::Error(js.str(""_kj)).As<v8::Object>();
+          jsg::check(err->Set(
+              js.v8Context(), js.str("name"_kj), js.str("Cross Request Promise Resolve"_kj)));
+          auto stack = jsg::check(err->Get(js.v8Context(), js.str("stack"_kj)));
+          KJ_LOG(WARNING, kj::str("NOSENTRY ", stack));
+
           // The promise tag is generally opaque except for right here. The tag
           // wraps an instanceof kj::Own<IoCrossContextExecutor>, which wraps an atomically
           // refcounted pointer to the DeleteQueue for the correct isolate.