Replace OwnPtr with WTF::Optional for optional recorders.

Source/core/paint/SVGContainerPainter.cpp

 // Copyright 2014 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 "config.h"
 #include "core/paint/SVGContainerPainter.h"
 
 #include "core/layout/svg/LayoutSVGContainer.h"
 #include "core/layout/svg/LayoutSVGViewportContainer.h"
 #include "core/layout/svg/SVGLayoutSupport.h"
 #include "core/paint/FloatClipRecorder.h"
 #include "core/paint/ObjectPainter.h"
 #include "core/paint/PaintInfo.h"
 #include "core/paint/SVGPaintContext.h"
 #include "core/paint/TransformRecorder.h"
 #include "core/svg/SVGSVGElement.h"
+#include "wtf/Optional.h"
 
 namespace blink {
 
 void SVGContainerPainter::paint(const PaintInfo& paintInfo)
 {
     // Spec: groups w/o children still may render filter content.
     if (!m_layoutSVGContainer.firstChild() && !m_layoutSVGContainer.selfWillPaint())
         return;
 
     FloatRect boundingBox = m_layoutSVGContainer.paintInvalidationRectInLocalCoordinates();
     if (!paintInfo.intersectsCullRect(m_layoutSVGContainer.localToParentTransform(), boundingBox))
         return;
 
     // Spec: An empty viewBox on the <svg> element disables rendering.
     ASSERT(m_layoutSVGContainer.element());
     if (isSVGSVGElement(*m_layoutSVGContainer.element()) && toSVGSVGElement(*m_layoutSVGContainer.element()).hasEmptyViewBox())
         return;
 
     PaintInfo paintInfoBeforeFiltering(paintInfo);
     paintInfoBeforeFiltering.updateCullRectForSVGTransform(m_layoutSVGContainer.localToParentTransform());
     TransformRecorder transformRecorder(*paintInfoBeforeFiltering.context, m_layoutSVGContainer, m_layoutSVGContainer.localToParentTransform());
     {
-        OwnPtr<FloatClipRecorder> clipRecorder;
+        Optional<FloatClipRecorder> clipRecorder;
         if (m_layoutSVGContainer.isSVGViewportContainer() && SVGLayoutSupport::isOverflowHidden(&m_layoutSVGContainer)) {
             FloatRect viewport = m_layoutSVGContainer.localToParentTransform().inverse().mapRect(toLayoutSVGViewportContainer(m_layoutSVGContainer).viewport());
-            clipRecorder = adoptPtr(new FloatClipRecorder(*paintInfoBeforeFiltering.context, m_layoutSVGContainer, paintInfoBeforeFiltering.phase, viewport));
+            clipRecorder.emplace(*paintInfoBeforeFiltering.context, m_layoutSVGContainer, paintInfoBeforeFiltering.phase, viewport);
         }
 
         SVGPaintContext paintContext(m_layoutSVGContainer, paintInfoBeforeFiltering);
         bool continueRendering = true;
         if (paintContext.paintInfo().phase == PaintPhaseForeground)
             continueRendering = paintContext.applyClipMaskAndFilterIfNecessary();
 
         if (continueRendering) {
             paintContext.paintInfo().updatePaintingRootForChildren(&m_layoutSVGContainer);
             for (LayoutObject* child = m_layoutSVGContainer.firstChild(); child; child = child->nextSibling())
                 child->paint(paintContext.paintInfo(), IntPoint());
         }
     }
 
     if (paintInfoBeforeFiltering.phase == PaintPhaseForeground && m_layoutSVGContainer.style()->outlineWidth() && m_layoutSVGContainer.style()->visibility() == VISIBLE) {
         LayoutRect layoutBoundingBox(boundingBox);
         ObjectPainter(m_layoutSVGContainer).paintOutline(paintInfoBeforeFiltering, layoutBoundingBox, layoutBoundingBox);
     }
 }
 
 } // namespace blink