[V8] Make String::CanMakeExternal ignore the length of new strings

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 2679a363f7fc0c0b8227348378e471cfbdd75f0f..824edf699c201745c38065190566c3ee1ab58d8a 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -5971,14 +5971,11 @@ bool v8::String::MakeExternal(
 
 bool v8::String::CanMakeExternal() {
   i::Handle<i::String> obj = Utils::OpenHandle(this);
-  i::Isolate* isolate = obj->GetIsolate();
+  if (obj->IsExternalString()) return false;
 
   // Old space strings should be externalized.
-  if (!isolate->heap()->new_space()->Contains(*obj)) return true;
-  int size = obj->Size();  // Byte size of the original string.
-  if (size <= i::ExternalString::kShortSize) return false;
-  i::StringShape shape(*obj);
-  return !shape.IsExternal();
+  i::Isolate* isolate = obj->GetIsolate();
+  return !isolate->heap()->new_space()->Contains(*obj);
 }