Reuse existing paint property node is possible

third_party/WebKit/Source/core/paint/ObjectPaintProperties.h

 // Copyright 2015 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.
 
 #ifndef ObjectPaintProperties_h
 #define ObjectPaintProperties_h
 
 #include "core/CoreExport.h"
 #include "platform/geometry/LayoutPoint.h"
 #include "platform/graphics/paint/ClipPaintPropertyNode.h"
@@ skipping 74 matching lines @@
     // These setters should only be used by PaintPropertyTreeBuilder.
     void setPaintOffsetTranslation(PassRefPtr<TransformPaintPropertyNode> paintOffset) { m_paintOffsetTranslation = paintOffset; }
     void setTransform(PassRefPtr<TransformPaintPropertyNode> transform) { m_transform = transform; }
     void setEffect(PassRefPtr<EffectPaintPropertyNode> effect) { m_effect = effect; }
     void setCssClip(PassRefPtr<ClipPaintPropertyNode> clip) { m_cssClip = clip; }
     void setCssClipFixedPosition(PassRefPtr<ClipPaintPropertyNode> clip) { m_cssClipFixedPosition = clip; }
     void setOverflowClip(PassRefPtr<ClipPaintPropertyNode> clip) { m_overflowClip = clip; }
     void setPerspective(PassRefPtr<TransformPaintPropertyNode> perspective) { m_perspective = perspective; }
     void setSvgLocalToBorderBoxTransform(PassRefPtr<TransformPaintPropertyNode> transform)
     {
-        DCHECK(!scrollTranslation()) << "SVG elements cannot scroll so there should never be both a scroll translation and an SVG local to border box transform.";
+        DCHECK(!scrollTranslation() || !transform) << "SVG elements cannot scroll so there should never be both a scroll translation and an SVG local to border box transform.";
         m_svgLocalToBorderBoxTransform = transform;
     }
     void setScrollTranslation(PassRefPtr<TransformPaintPropertyNode> translation)
     {
-        DCHECK(!svgLocalToBorderBoxTransform()) << "SVG elements cannot scroll so there should never be both a scroll translation and an SVG local to border box transform.";
+        DCHECK(!svgLocalToBorderBoxTransform() || !translation) << "SVG elements cannot scroll so there should never be both a scroll translation and an SVG local to border box transform.";
         m_scrollTranslation = translation;
     }
     void setScrollbarPaintOffset(PassRefPtr<TransformPaintPropertyNode> paintOffset) { m_scrollbarPaintOffset = paintOffset; }
     void setLocalBorderBoxProperties(std::unique_ptr<LocalBorderBoxProperties> properties) { m_localBorderBoxProperties = std::move(properties); }
 
     RefPtr<TransformPaintPropertyNode> m_paintOffsetTranslation;
     RefPtr<TransformPaintPropertyNode> m_transform;
     RefPtr<EffectPaintPropertyNode> m_effect;
     RefPtr<ClipPaintPropertyNode> m_cssClip;
     RefPtr<ClipPaintPropertyNode> m_cssClipFixedPosition;
     RefPtr<ClipPaintPropertyNode> m_overflowClip;
     RefPtr<TransformPaintPropertyNode> m_perspective;
     // TODO(pdr): Only LayoutSVGRoot needs this and it should be moved there.
     RefPtr<TransformPaintPropertyNode> m_svgLocalToBorderBoxTransform;
     RefPtr<TransformPaintPropertyNode> m_scrollTranslation;
     RefPtr<TransformPaintPropertyNode> m_scrollbarPaintOffset;
 
     std::unique_ptr<LocalBorderBoxProperties> m_localBorderBoxProperties;
 };
 
 } // namespace blink
 
 #endif // ObjectPaintProperties_h