Filter out invalid slots in store buffer eagerly during object transition.

src/heap/heap.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_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 #include <map>
 
@@ skipping 1058 matching lines @@
   // Write barrier support for address[offset] = o.
   INLINE(void RecordWrite(Address address, int offset));
 
   // Write barrier support for address[start : start + len[ = o.
   INLINE(void RecordWrites(Address address, int start, int len));
 
   Address* store_buffer_top_address() {
     return reinterpret_cast<Address*>(&roots_[kStoreBufferTopRootIndex]);
   }
 
+  void ClearRecordedSlot(HeapObject* object, Object** slot);
+
   // ===========================================================================
   // Incremental marking API. ==================================================
   // ===========================================================================
 
   // Start incremental marking and ensure that idle time handler can perform
   // incremental steps.
   void StartIdleIncrementalMarking();
 
   // Starts incremental marking assuming incremental marking is currently
   // stopped.
@@ skipping 1541 matching lines @@
 
  private:
   friend class NewSpace;
   DISALLOW_COPY_AND_ASSIGN(InlineAllocationObserver);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_H_