[modules] Add CHECK to dynamic import

https://crrev.com/c/3110611 has landed, thus we can revert the temporary
workaround.

Bug: chromium:1237730
Change-Id: Ieb39ff07baddd03dc41c716d921496eb4d539fae
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3114137
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76449}

src/execution/isolate.cc

@@ -4252,18 +4252,16 @@ MaybeHandle<JSPromise> NewRejectedPromise(Isolate* isolate,
 }  // namespace
 
 MaybeHandle<JSPromise> Isolate::RunHostImportModuleDynamicallyCallback(
-    MaybeHandle<Script> maybe_referrer, Handle<Object> specifier,
+    Handle<Script> referrer, Handle<Object> specifier,
     MaybeHandle<Object> maybe_import_assertions_argument) {
   v8::Local<v8::Context> api_context =
       v8::Utils::ToLocal(Handle<Context>(native_context()));
   DCHECK(host_import_module_dynamically_callback_ == nullptr ||
          host_import_module_dynamically_with_import_assertions_callback_ ==
              nullptr);
-  Handle<Script> referrer;
-  if (!maybe_referrer.ToHandle(&referrer) ||
-      (host_import_module_dynamically_callback_ == nullptr &&
-       host_import_module_dynamically_with_import_assertions_callback_ ==
-           nullptr)) {
+  if (host_import_module_dynamically_callback_ == nullptr &&
+      host_import_module_dynamically_with_import_assertions_callback_ ==
+          nullptr) {
     Handle<Object> exception =
         factory()->NewError(error_function(), MessageTemplate::kUnsupported);
     return NewRejectedPromise(this, api_context, exception);

src/execution/isolate.h

@@ -1666,7 +1666,7 @@ class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
   void SetHostImportModuleDynamicallyCallback(
       HostImportModuleDynamicallyWithImportAssertionsCallback callback);
   MaybeHandle<JSPromise> RunHostImportModuleDynamicallyCallback(
-      MaybeHandle<Script> referrer, Handle<Object> specifier,
+      Handle<Script> referrer, Handle<Object> specifier,
       MaybeHandle<Object> maybe_import_assertions_argument);
 
   void SetHostInitializeImportMetaObjectCallback(

src/runtime/runtime-module.cc

@@ -13,11 +13,11 @@ namespace v8 {
 namespace internal {
 
 namespace {
-MaybeHandle<Script> GetEvalOrigin(Isolate* isolate, Script origin_script) {
+Handle<Script> GetEvalOrigin(Isolate* isolate, Script origin_script) {
   DisallowGarbageCollection no_gc;
   while (origin_script.has_eval_from_shared()) {
     HeapObject maybe_script = origin_script.eval_from_shared().script();
-    if (V8_UNLIKELY(!maybe_script.IsScript())) return kNullMaybeHandle;
+    CHECK(maybe_script.IsScript());
     origin_script = Script::cast(maybe_script);
   }
   return handle(origin_script, isolate);
@@ -37,9 +37,8 @@ RUNTIME_FUNCTION(Runtime_DynamicImportCall) {
     import_assertions = args.at<Object>(2);
   }
 
-  MaybeHandle<Script> referrer_script =
+  Handle<Script> referrer_script =
       GetEvalOrigin(isolate, Script::cast(function->shared().script()));
-
   RETURN_RESULT_OR_FAILURE(isolate,
                            isolate->RunHostImportModuleDynamicallyCallback(
                                referrer_script, specifier, import_assertions));