Check the next chain of a slotchange event correctly on a slotchange at a fallback slot

third_party/WebKit/Source/core/html/HTMLSlotElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp b/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
index ee7300a11fa72921c1c503c42a1d24486d30e447..670f3fe39413bcc268ea6467c16628e6b1adf8ff 100644
--- a/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSlotElement.cpp
@@ -321,11 +321,8 @@ void HTMLSlotElement::enqueueSlotChangeEvent()
     DCHECK(root);
     DCHECK(root->isV1());
     root->owner()->setNeedsDistributionRecalc();
-
-    if (ShadowRoot* parentShadowRoot = v1ShadowRootOfParent()) {
-        if (HTMLSlotElement* next = parentShadowRoot->ensureSlotAssignment().findSlot(*this))
-            next->enqueueSlotChangeEvent();
-    }
+    // Check slotchange recursively since this slotchange may cause another slotchange.
+    checkSlotChange();
 }
 
 bool HTMLSlotElement::hasAssignedNodesSlow() const