Merge WebKit at r63859 : Initial merge by git.

Change-Id: Ie8096c63ec7c991c9a9cba8bdd9c3b74a3b8ed62

1 files changed, 47 insertions, 6 deletions

diff --git a/WebCore/rendering/RenderSVGResourceContainer.h b/WebCore/rendering/RenderSVGResourceContainer.h
index 54617bb..5f1c828 100644
--- a/WebCore/rendering/RenderSVGResourceContainer.h
+++ b/WebCore/rendering/RenderSVGResourceContainer.h
@@ -26,6 +26,7 @@
 
 #include "SVGStyledTransformableElement.h"
 #include "RenderSVGResource.h"
+#include "RenderSVGShadowTreeRootContainer.h"
 
 namespace WebCore {
 
@@ -35,8 +36,7 @@ public:
     RenderSVGResourceContainer(SVGStyledElement* node)
         : RenderSVGHiddenContainer(node)
         , RenderSVGResource()
-        // FIXME: Should probably be using getIdAttribute rather than idForStyleResolution.
-        , m_id(node->hasID() ? node->idForStyleResolution() : nullAtom)
+        , m_id(node->hasID() ? node->getIdAttribute() : nullAtom)
     {
         ASSERT(node->document());
         node->document()->accessSVGExtensions()->addResource(m_id, this);
@@ -57,9 +57,7 @@ public:
 
         // Remove old id, that is guaranteed to be present in cache
         extensions->removeResource(m_id);
-
-        // FIXME: Should probably be using getIdAttribute rather than idForStyleResolution.
-        m_id = node()->hasID() ? static_cast<Element*>(node())->idForStyleResolution() : nullAtom;
+        m_id = static_cast<Element*>(node())->getIdAttribute();
 
         // It's possible that an element is referencing us with the new id, and has to be notified that we're existing now
         if (extensions->isPendingResource(m_id)) {
@@ -84,7 +82,8 @@ public:
     virtual bool drawsContents() { return false; }
 
     virtual RenderSVGResourceContainer* toRenderSVGResourceContainer() { return this; }
-    
+    virtual bool childElementReferencesResource(const SVGRenderStyle*, const String&) const { return false; }
+
     static AffineTransform transformOnNonScalingStroke(RenderObject* object, const AffineTransform resourceTransform)
     {
         if (!object->isRenderPath())
@@ -96,6 +95,48 @@ public:
         return transform;
     }
 
+    bool containsCyclicReference(const Node* startNode) const
+    {
+        ASSERT(startNode->document());
+    
+        for (Node* node = startNode->firstChild(); node; node = node->nextSibling()) {
+            if (!node->isSVGElement())
+                continue;
+    
+            RenderObject* renderer = node->renderer();
+            if (!renderer)
+                continue;
+    
+            RenderStyle* style = renderer->style();
+            if (!style)
+                continue;
+    
+            const SVGRenderStyle* svgStyle = style->svgStyle();
+            ASSERT(svgStyle);
+    
+            // Let the class inheriting from us decide whether the child element references ourselves.
+            if (childElementReferencesResource(svgStyle, m_id))
+                return true;
+
+            // Dive into shadow tree to check for cycles there.
+            if (node->hasTagName(SVGNames::useTag)) {
+                ASSERT(renderer->isSVGShadowTreeRootContainer());
+                if (Node* shadowRoot = static_cast<RenderSVGShadowTreeRootContainer*>(renderer)->rootElement()) {
+                    if (containsCyclicReference(shadowRoot))
+                        return true;
+                }
+
+            }
+
+            if (node->hasChildNodes()) {
+                if (containsCyclicReference(node))
+                    return true;
+            }
+        }
+    
+        return false;
+    }
+
 private:
     AtomicString m_id;
 };