Remove now-unused Visitor::m_isGlobalMarkingVisitor field.

third_party/WebKit/Source/platform/heap/HeapPage.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 21 matching lines @@
 #define HeapPage_h
 
 #include "platform/PlatformExport.h"
 #include "platform/heap/BlinkGC.h"
 #include "platform/heap/GCInfo.h"
 #include "platform/heap/ThreadState.h"
 #include "platform/heap/Visitor.h"
 #include "wtf/AddressSanitizer.h"
 #include "wtf/Allocator.h"
 #include "wtf/Assertions.h"
-#include "wtf/Atomics.h"
 #include "wtf/ContainerAnnotations.h"
 #include "wtf/Forward.h"
 #include "wtf/PageAllocator.h"
 #include <stdint.h>
 
 namespace blink {
 
 const size_t blinkPageSizeLog2 = 17;
 const size_t blinkPageSize = 1 << blinkPageSizeLog2;
 const size_t blinkPageOffsetMask = blinkPageSize - 1;
@@ skipping 834 matching lines @@
         SET_MEMORY_ACCESSIBLE(result, allocationSize - sizeof(HeapObjectHeader));
         ASSERT(findPageFromAddress(headerAddress + allocationSize - 1));
         return result;
     }
     return outOfLineAllocate(allocationSize, gcInfoIndex);
 }
 
 } // namespace blink
 
 #endif // HeapPage_h