[Property wrappers] Be sure to record the original value initializer!

Author: DougGregor

lib/Sema/TypeCheckStorage.cpp

@@ -2436,7 +2436,8 @@ PropertyWrapperBackingPropertyInfoRequest::evaluate(Evaluator &evaluator,
   }
 
   // Get the property wrapper information.
-  if (!var->allAttachedPropertyWrappersHaveInitialValueInit()) {
+  if (!var->allAttachedPropertyWrappersHaveInitialValueInit() &&
+      !originalInitialValue) {
     return PropertyWrapperBackingPropertyInfo(
         backingVar, storageVar, nullptr, nullptr, nullptr);
   }