Let HTMLTablePartElement::findParentTable() about come across shadow boundary.

Source/core/dom/NodeRenderingTraversal.h

Index: Source/core/dom/NodeRenderingTraversal.h
diff --git a/Source/core/dom/NodeRenderingTraversal.h b/Source/core/dom/NodeRenderingTraversal.h
index 6fb020d33fac98f566ce12ace2ae9dfd75e086bd..23bee1db1b15f177235b8240178681967a1574ae 100644
--- a/Source/core/dom/NodeRenderingTraversal.h
+++ b/Source/core/dom/NodeRenderingTraversal.h
@@ -64,6 +64,7 @@ private:
     bool m_outOfComposition;
 };
 
+ContainerNode* parent(const Node*);
 ContainerNode* parent(const Node*, ParentDetails*);
 ContainerNode* parentSlow(const Node*, ParentDetails*);
 Node* nextSibling(const Node*);
@@ -76,6 +77,12 @@ Node* previousInScope(const Node*);
 Node* parentInScope(const Node*);
 Node* lastChildInScope(const Node*);
 
+inline ContainerNode* parent(const Node* node)
+{
+    ParentDetails unusedDetails;
+    return parent(node, &unusedDetails);
+}
+
 inline ContainerNode* parent(const Node* node, ParentDetails* details)
 {
     if (!node->needsShadowTreeWalker()) {