Optimize @@species based on a global 'protector' cell

src/lookup.h

 // 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.
 
 #ifndef V8_LOOKUP_H_
 #define V8_LOOKUP_H_
 
 #include "src/factory.h"
 #include "src/isolate.h"
 #include "src/objects.h"
@@ skipping 238 matching lines @@
   int GetAccessorIndex() const;
   int GetConstantIndex() const;
   Handle<PropertyCell> GetPropertyCell() const;
   Handle<Object> GetAccessors() const;
   inline Handle<InterceptorInfo> GetInterceptor() const {
     DCHECK_EQ(INTERCEPTOR, state_);
     return handle(GetInterceptor(JSObject::cast(*holder_)), isolate_);
   }
   Handle<Object> GetDataValue() const;
   void WriteDataValue(Handle<Object> value);
+  void UpdateProtector();
 
  private:
   enum class InterceptorState {
     kUninitialized,
     kSkipNonMasking,
     kProcessNonMasking
   };
 
   Handle<Map> GetReceiverMap() const;
 
@@ skipping 66 matching lines @@
   Handle<JSReceiver> holder_;
   const Handle<JSReceiver> initial_holder_;
   uint32_t number_;
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_LOOKUP_H_