Refactor the Heap into ThreadHeap to prepare for per thread heaps

third_party/WebKit/Source/platform/heap/Visitor.cpp

 // Copyright 2016 The Chromium 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 "platform/heap/Visitor.h"
 
 #include "platform/heap/BlinkGC.h"
 #include "platform/heap/MarkingVisitor.h"
 #include "platform/heap/ThreadState.h"
 
 namespace blink {
 
 VisitorScope::VisitorScope(ThreadState* state, BlinkGC::GCType gcType)
     : m_state(state)
 {
     // See ThreadState::runScheduledGC() why we need to already be in a
     // GCForbiddenScope before any safe point is entered.
     m_state->enterGCForbiddenScope();
 
     ASSERT(m_state->checkThread());
 
     switch (gcType) {
     case BlinkGC::GCWithSweep:
     case BlinkGC::GCWithoutSweep:
-        m_visitor = adoptPtr(new MarkingVisitor<Visitor::GlobalMarking>());
+        m_visitor = adoptPtr(new MarkingVisitor<Visitor::GlobalMarking>(this));
         break;
     case BlinkGC::TakeSnapshot:
-        m_visitor = adoptPtr(new MarkingVisitor<Visitor::SnapshotMarking>());
+        m_visitor = adoptPtr(new MarkingVisitor<Visitor::SnapshotMarking>(this));
         break;
     case BlinkGC::ThreadTerminationGC:
-        m_visitor = adoptPtr(new MarkingVisitor<Visitor::ThreadLocalMarking>());
+        m_visitor = adoptPtr(new MarkingVisitor<Visitor::ThreadLocalMarking>(this));
         break;
     case BlinkGC::ThreadLocalWeakProcessing:
-        m_visitor = adoptPtr(new MarkingVisitor<Visitor::WeakProcessing>());
+        m_visitor = adoptPtr(new MarkingVisitor<Visitor::WeakProcessing>(this));
         break;
     default:
         ASSERT_NOT_REACHED();
     }
 }
 
 VisitorScope::~VisitorScope()
 {
     m_state->leaveGCForbiddenScope();
 }
 
 } // namespace blink