Revert of Fix old space check in IsSlotInBlackObject.

src/heap/mark-compact.cc

 // 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.
 
 #include "src/v8.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
@@ skipping 3041 matching lines @@
     heap()->IncrementPromotedObjectsSize(object_size);
     return true;
   }
 
   return false;
 }
 
 
 bool MarkCompactCollector::IsSlotInBlackObject(Page* p, Address slot) {
   // This function does not support large objects right now.
-  Space* owner = p->owner();
-  if (owner == heap_->lo_space() || owner == NULL) return true;
+  if (p->owner() == NULL) return true;
 
   uint32_t mark_bit_index = p->AddressToMarkbitIndex(slot);
   unsigned int start_index = mark_bit_index >> Bitmap::kBitsPerCellLog2;
   MarkBit::CellType index_in_cell = 1U
                                     << (mark_bit_index & Bitmap::kBitIndexMask);
   MarkBit::CellType* cells = p->markbits()->cells();
   Address cell_base = p->area_start();
   unsigned int cell_base_start_index = Bitmap::IndexToCell(
       Bitmap::CellAlignIndex(p->AddressToMarkbitIndex(cell_base)));
 
@@ skipping 1563 matching lines @@
   SlotsBuffer* buffer = *buffer_address;
   while (buffer != NULL) {
     SlotsBuffer* next_buffer = buffer->next();
     DeallocateBuffer(buffer);
     buffer = next_buffer;
   }
   *buffer_address = NULL;
 }
 }
 }  // namespace v8::internal