Revert "Remove OwnPtr from Blink."

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"
-#include "wtf/PtrUtil.h"
-#include <memory>
 
 namespace blink {
 
-std::unique_ptr<Visitor> Visitor::create(ThreadState* state, BlinkGC::GCType gcType)
+PassOwnPtr<Visitor> Visitor::create(ThreadState* state, BlinkGC::GCType gcType)
 {
     switch (gcType) {
     case BlinkGC::GCWithSweep:
     case BlinkGC::GCWithoutSweep:
-        return wrapUnique(new MarkingVisitor<Visitor::GlobalMarking>(state));
+        return adoptPtr(new MarkingVisitor<Visitor::GlobalMarking>(state));
     case BlinkGC::TakeSnapshot:
-        return wrapUnique(new MarkingVisitor<Visitor::SnapshotMarking>(state));
+        return adoptPtr(new MarkingVisitor<Visitor::SnapshotMarking>(state));
     case BlinkGC::ThreadTerminationGC:
-        return wrapUnique(new MarkingVisitor<Visitor::ThreadLocalMarking>(state));
+        return adoptPtr(new MarkingVisitor<Visitor::ThreadLocalMarking>(state));
     case BlinkGC::ThreadLocalWeakProcessing:
-        return wrapUnique(new MarkingVisitor<Visitor::WeakProcessing>(state));
+        return adoptPtr(new MarkingVisitor<Visitor::WeakProcessing>(state));
     default:
         ASSERT_NOT_REACHED();
     }
     return nullptr;
 }
 
 Visitor::Visitor(ThreadState* state, MarkingMode markingMode)
     : VisitorHelper(state)
     , m_markingMode(markingMode)
 {
     // See ThreadState::runScheduledGC() why we need to already be in a
     // GCForbiddenScope before any safe point is entered.
     state->enterGCForbiddenScope();
 
     ASSERT(state->checkThread());
 }
 
 Visitor::~Visitor()
 {
     state()->leaveGCForbiddenScope();
 }
 
 } // namespace blink