Remove the global Strength enum class completely.

src/runtime/runtime-classes.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/runtime/runtime-utils.h"
 
 #include <stdlib.h>
 #include <limits>
 
 #include "src/arguments.h"
@@ skipping 106 matching lines @@
       THROW_NEW_ERROR(
           isolate,
           NewTypeError(MessageTemplate::kExtendsValueNotFunction, super_class),
           Object);
     }
   }
 
   Handle<Map> map =
       isolate->factory()->NewMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
   map->set_is_prototype_map(true);
-  if (constructor->map()->is_strong()) {
-    map->set_is_strong();
-    if (super_class->IsNull()) {
-      // Strong class is not permitted to extend null.
-      THROW_NEW_ERROR(isolate, NewTypeError(MessageTemplate::kStrongExtendNull),
-                      Object);
-    }
-  }
   Map::SetPrototype(map, prototype_parent);
   map->SetConstructor(*constructor);
   Handle<JSObject> prototype = isolate->factory()->NewJSObjectFromMap(map);
 
   if (!super_class->IsTheHole()) {
     // Derived classes, just like builtins, don't create implicit receivers in
     // [[construct]]. Instead they just set up new.target and call into the
     // constructor. Hence we can reuse the builtins construct stub for derived
     // classes.
     Handle<Code> stub(isolate->builtins()->JSBuiltinsConstructStubForDerived());
@@ skipping 54 matching lines @@
       isolate, result, DefineClass(isolate, super_class, constructor,
                                    start_position, end_position));
   return *result;
 }
 
 
 RUNTIME_FUNCTION(Runtime_FinalizeClassDefinition) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, constructor, 0);
-  CONVERT_ARG_HANDLE_CHECKED(JSObject, prototype, 1);
-
   JSObject::MigrateSlowToFast(constructor, 0, "RuntimeToFastProperties");
-
-  if (constructor->map()->is_strong()) {
-    DCHECK(prototype->map()->is_strong());
-    MAYBE_RETURN(JSReceiver::SetIntegrityLevel(prototype, FROZEN,
-                                               Object::THROW_ON_ERROR),
-                 isolate->heap()->exception());
-    MAYBE_RETURN(JSReceiver::SetIntegrityLevel(constructor, FROZEN,
-                                               Object::THROW_ON_ERROR),
-                 isolate->heap()->exception());
-  }
   return *constructor;
 }
 
 static MaybeHandle<Object> LoadFromSuper(Isolate* isolate,
                                          Handle<Object> receiver,
                                          Handle<JSObject> home_object,
                                          Handle<Name> name) {
   if (home_object->IsAccessCheckNeeded() &&
       !isolate->MayAccess(handle(isolate->context()), home_object)) {
     isolate->ReportFailedAccessCheck(home_object);
@@ skipping 200 matching lines @@
 
 RUNTIME_FUNCTION(Runtime_GetSuperConstructor) {
   SealHandleScope shs(isolate);
   DCHECK_EQ(1, args.length());
   CONVERT_ARG_CHECKED(JSFunction, active_function, 0);
   return active_function->map()->prototype();
 }
 
 }  // namespace internal
 }  // namespace v8