Move Node::lastDescendantOrSelf() to NodeTraversal and rename to lastWithinOrSelf()

Source/core/editing/ReplaceSelectionCommand.cpp

Index: Source/core/editing/ReplaceSelectionCommand.cpp
diff --git a/Source/core/editing/ReplaceSelectionCommand.cpp b/Source/core/editing/ReplaceSelectionCommand.cpp
index 746703cbb292845d12811408f2d2c4243e528b5f..656fa25a976618de64307dfa58c4296a42ecc420 100644
--- a/Source/core/editing/ReplaceSelectionCommand.cpp
+++ b/Source/core/editing/ReplaceSelectionCommand.cpp
@@ -1487,7 +1487,7 @@ void ReplaceSelectionCommand::updateNodesInserted(Node *node)
     if (m_startOfInsertedContent.isNull())
         m_startOfInsertedContent = firstPositionInOrBeforeNode(node);
 
-    m_endOfInsertedContent = lastPositionInOrAfterNode(&node->lastDescendantOrSelf());
+    m_endOfInsertedContent = lastPositionInOrAfterNode(&NodeTraversal::lastWithinOrSelf(*node));
 }
 
 // During simple pastes, where we're just pasting a text node into a run of text, we insert the text node