Reland of "Tracking reference filter mutation via SVGElementProxy"

third_party/WebKit/Source/core/svg/SVGFilterElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006 Rob Buis <buis@kde.org>
  * Copyright (C) 2006 Samuel Weinig <sam.weinig@gmail.com>
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #include "core/svg/SVGFilterElement.h"
 
 #include "core/frame/UseCounter.h"
 #include "core/layout/svg/LayoutSVGResourceFilter.h"
-#include "core/svg/SVGResourceClient.h"
+#include "core/svg/SVGElementProxy.h"
 
 namespace blink {
 
 inline SVGFilterElement::SVGFilterElement(Document& document)
     : SVGElement(SVGNames::filterTag, document),
       SVGURIReference(this),
       m_x(SVGAnimatedLength::create(this,
                                     SVGNames::xAttr,
                                     SVGLength::create(SVGLengthMode::Width))),
       m_y(SVGAnimatedLength::create(this,
@@ skipping 37 matching lines @@
 
 DEFINE_NODE_FACTORY(SVGFilterElement)
 
 DEFINE_TRACE(SVGFilterElement) {
   visitor->trace(m_x);
   visitor->trace(m_y);
   visitor->trace(m_width);
   visitor->trace(m_height);
   visitor->trace(m_filterUnits);
   visitor->trace(m_primitiveUnits);
-  visitor->trace(m_clientsToAdd);
+  visitor->trace(m_elementProxySet);
   SVGElement::trace(visitor);
   SVGURIReference::trace(visitor);
 }
 
 void SVGFilterElement::svgAttributeChanged(const QualifiedName& attrName) {
   bool isXYWH = attrName == SVGNames::xAttr || attrName == SVGNames::yAttr ||
                 attrName == SVGNames::widthAttr ||
                 attrName == SVGNames::heightAttr;
   if (isXYWH)
     updateRelativeLengthsInformation();
@@ skipping 17 matching lines @@
 
   if (change.byParser)
     return;
 
   if (LayoutObject* object = layoutObject())
     object->setNeedsLayoutAndFullPaintInvalidation(
         LayoutInvalidationReason::ChildChanged);
 }
 
 LayoutObject* SVGFilterElement::createLayoutObject(const ComputedStyle&) {
-  LayoutSVGResourceFilter* layoutObject = new LayoutSVGResourceFilter(this);
-
-  for (SVGResourceClient* client : m_clientsToAdd)
-    layoutObject->addResourceClient(client);
-  m_clientsToAdd.clear();
-
-  return layoutObject;
+  return new LayoutSVGResourceFilter(this);
 }
 
 bool SVGFilterElement::selfHasRelativeLengths() const {
   return m_x->currentValue()->isRelative() ||
          m_y->currentValue()->isRelative() ||
          m_width->currentValue()->isRelative() ||
          m_height->currentValue()->isRelative();
 }
 
-void SVGFilterElement::addClient(SVGResourceClient* client) {
-  ASSERT(client);
-  m_clientsToAdd.add(client);
-}
-
-void SVGFilterElement::removeClient(SVGResourceClient* client) {
-  ASSERT(client);
-  m_clientsToAdd.remove(client);
+SVGElementProxySet& SVGFilterElement::elementProxySet() {
+  if (!m_elementProxySet)
+    m_elementProxySet = new SVGElementProxySet;
+  return *m_elementProxySet;
 }
 
 }  // namespace blink