Reland of Remove slots that point to unboxed doubles from the StoreBuffer/SlotsBuffer.

src/heap/mark-compact.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_HEAP_MARK_COMPACT_H_
 #define V8_HEAP_MARK_COMPACT_H_
 
 #include "src/base/bits.h"
 #include "src/heap/spaces.h"
 
@@ skipping 342 matching lines @@
     buffer->Add(slot);
     return true;
   }
 
   static bool IsTypedSlot(ObjectSlot slot);
 
   static bool AddTo(SlotsBufferAllocator* allocator,
                     SlotsBuffer** buffer_address, SlotType type, Address addr,
                     AdditionMode mode);
 
+  // Removes all occurrences of given slot from the chain of slots buffers.
+  static void RemoveSlot(SlotsBuffer* buffer, ObjectSlot slot_to_remove);
+
   static const int kNumberOfElements = 1021;
 
  private:
   static const int kChainLengthThreshold = 15;
 
   intptr_t idx_;
   intptr_t chain_length_;
   SlotsBuffer* next_;
   ObjectSlot slots_[kNumberOfElements];
 };
@@ skipping 593 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_MARK_COMPACT_H_