Remove lazy sweeping of new space and corresponding complicated pointer updating logic.

src/heap/store-buffer-inl.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_STORE_BUFFER_INL_H_
 #define V8_STORE_BUFFER_INL_H_
 
 #include "src/heap/store-buffer.h"
 
 namespace v8 {
@@ skipping 31 matching lines @@
     old_top_ = top;
     old_buffer_is_sorted_ = false;
     old_buffer_is_filtered_ = false;
     if (top >= old_limit_) {
       DCHECK(callback_ != NULL);
       (*callback_)(heap_, MemoryChunk::FromAnyPointerAddress(heap_, addr),
                    kStoreBufferFullEvent);
     }
   }
 }
-
-
-void StoreBuffer::ClearDeadObject(HeapObject* object) {
-  Address& map_field = Memory::Address_at(object->address());
-  if (heap_->map_space()->Contains(map_field)) {
-    map_field = NULL;
-  }
-}
 }
 }  // namespace v8::internal
 
 #endif  // V8_STORE_BUFFER_INL_H_