Ensure slow properties for simple {__proto__:null} literals.

src/parsing/parser.h

 // Copyright 2012 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_PARSING_PARSER_H_
 #define V8_PARSING_PARSER_H_
 
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/base/compiler-specific.h"
@@ skipping 732 matching lines @@
   V8_INLINE bool IsConstructor(const AstRawString* identifier) const {
     return identifier == ast_value_factory()->constructor_string();
   }
 
   V8_INLINE bool IsName(const AstRawString* identifier) const {
     return identifier == ast_value_factory()->name_string();
   }
 
   V8_INLINE static bool IsBoilerplateProperty(
       ObjectLiteral::Property* property) {
-    return ObjectLiteral::IsBoilerplateProperty(property);
+    return !property->IsPrototype();
   }
 
   V8_INLINE bool IsNative(Expression* expr) const {
     DCHECK_NOT_NULL(expr);
     return expr->IsVariableProxy() &&
            expr->AsVariableProxy()->raw_name() ==
                ast_value_factory()->native_string();
   }
 
   V8_INLINE static bool IsArrayIndex(const AstRawString* string,
@@ skipping 450 matching lines @@
 
  private:
   ParserTarget** variable_;
   ParserTarget* previous_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PARSING_PARSER_H_