Support slotchange event

third_party/WebKit/Source/core/dom/Node.cpp

Index: third_party/WebKit/Source/core/dom/Node.cpp
diff --git a/third_party/WebKit/Source/core/dom/Node.cpp b/third_party/WebKit/Source/core/dom/Node.cpp
index 7ff26433da8eeb4b6d0e1727615d10484e84f811..d931b496bd20ef11cbcad99442b624d6c6ef83d8 100644
--- a/third_party/WebKit/Source/core/dom/Node.cpp
+++ b/third_party/WebKit/Source/core/dom/Node.cpp
@@ -2165,9 +2165,6 @@ StaticNodeList* Node::getDestinationInsertionPoints()
 
 HTMLSlotElement* Node::assignedSlot() const
 {
-#if DCHECK_IS_ON()
-    DCHECK(!needsDistributionRecalc());
-#endif
     Element* parent = parentElement();
     ShadowRoot* root = parent ? parent->youngestShadowRoot() : nullptr;
     if (root && root->isV1())
@@ -2250,6 +2247,15 @@ void Node::setCustomElementState(CustomElementState newState)
         toElement(this)->pseudoStateChanged(CSSSelector::PseudoUnresolved);
 }
 
+void Node::updateAssignmentForInsertedInto(ContainerNode* insertionPoint)
+{
+    if (isShadowHost(insertionPoint)) {
+        ShadowRoot* root = insertionPoint->youngestShadowRoot();
+        if (root && root->isV1())
+            root->assignV1();
+    }
+}
+
 DEFINE_TRACE(Node)
 {
     visitor->trace(m_parentOrShadowHostNode);