Use the LookupIterator for SetElement and friends

src/json-parser.h

 // Copyright 2011 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_JSON_PARSER_H_
 #define V8_JSON_PARSER_H_
 
 #include "src/v8.h"
 
 #include "src/char-predicates-inl.h"
@@ skipping 307 matching lines @@
   }
 
   if (c0_ == '"') {
     // Successfully parsed index, parse and store element.
     AdvanceSkipWhitespace();
 
     if (c0_ == ':') {
       AdvanceSkipWhitespace();
       Handle<Object> value = ParseJsonValue();
       if (!value.is_null()) {
-        JSObject::SetOwnElement(json_object, index, value, SLOPPY).Assert();
+        JSObject::SetOwnElementIgnoreAttributes(json_object, index, value, NONE)
+            .Assert();
         return kElementFound;
       } else {
         return kNullHandle;
       }
     }
   }
   return kElementNotFound;
 }
 
 // Parse a JSON object. Position must be right at '{'.
@@ skipping 495 matching lines @@
 
   DCHECK_EQ('"', c0_);
   // Advance past the last '"'.
   AdvanceSkipWhitespace();
   return result;
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_JSON_PARSER_H_