Add support for SVG Clip paths in HTML

Source/core/svg/SVGClipPathElement.cpp

Index: Source/core/svg/SVGClipPathElement.cpp
diff --git a/Source/core/svg/SVGClipPathElement.cpp b/Source/core/svg/SVGClipPathElement.cpp
index 4de9d37af7a77d7f5b95606563cd4b34c9f1efb8..bb37630eef3f5d496236518a7f2c2013ef990ffb 100644
--- a/Source/core/svg/SVGClipPathElement.cpp
+++ b/Source/core/svg/SVGClipPathElement.cpp
@@ -37,6 +37,14 @@ inline SVGClipPathElement::SVGClipPathElement(Document& document)
 
 DEFINE_NODE_FACTORY(SVGClipPathElement)
 
+void SVGClipPathElement::trace(Visitor* visitor)
+{
+#if ENABLE(OILPAN)
+    visitor->trace(m_clientsToAdd);
+#endif
+    SVGGraphicsElement::trace(visitor);
+}
+
 bool SVGClipPathElement::isSupportedAttribute(const QualifiedName& attrName)
 {
     DEFINE_STATIC_LOCAL(HashSet<QualifiedName>, supportedAttributes, ());
@@ -90,7 +98,26 @@ void SVGClipPathElement::childrenChanged(const ChildrenChange& change)
 
 RenderObject* SVGClipPathElement::createRenderer(RenderStyle*)
 {
-    return new RenderSVGResourceClipper(this);
+    RenderSVGResourceClipper* renderer = new RenderSVGResourceClipper(this);
+
+    WillBeHeapHashSet<RefPtrWillBeMember<Node> >::iterator layerEnd = m_clientsToAdd.end();
+    for (WillBeHeapHashSet<RefPtrWillBeMember<Node> >::iterator it = m_clientsToAdd.begin(); it != layerEnd; ++it)
+        renderer->addClientRenderLayer(it->get());
+    m_clientsToAdd.clear();
+
+    return renderer;
+}
+
+void SVGClipPathElement::addClient(Node* client)
+{
+    ASSERT(client);
+    m_clientsToAdd.add(client);
+}
+
+void SVGClipPathElement::removeClient(Node* client)
+{
+    ASSERT(client);
+    m_clientsToAdd.remove(client);
 }
 
 }