Get rid of JSArray::Expand and friends

src/json-stringifier.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_JSON_STRINGIFIER_H_
 #define V8_JSON_STRINGIFIER_H_
 
 #include "src/v8.h"
 
 #include "src/conversions.h"
@@ skipping 262 matching lines @@
     for (int i = 0; i < length; i++) {
       if (elements->get(i) == *object) {
         AllowHeapAllocation allow_to_return_error;
         Handle<Object> error =
             factory()->NewTypeError(MessageTemplate::kCircularStructure);
         isolate_->Throw(*error);
         return EXCEPTION;
       }
     }
   }
-  JSArray::EnsureSize(stack_, length + 1);
+  JSArray::SetLength(stack_, length + 1);
   FixedArray::cast(stack_->elements())->set(length, *object);
-  stack_->set_length(Smi::FromInt(length + 1));
   return SUCCESS;
 }
 
 
 void BasicJsonStringifier::StackPop() {
   int length = Smi::cast(stack_->length())->value();
   stack_->set_length(Smi::FromInt(length - 1));
 }
 
 
@@ skipping 382 matching lines @@
       SerializeString_<uint8_t, uc16>(object);
     } else {
       SerializeString_<uc16, uc16>(object);
     }
   }
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_JSON_STRINGIFIER_H_