Avoid duplicate null check in ReplaceSelectionCommand::pastLastLeaf()

Source/core/editing/ReplaceSelectionCommand.h

Index: Source/core/editing/ReplaceSelectionCommand.h
diff --git a/Source/core/editing/ReplaceSelectionCommand.h b/Source/core/editing/ReplaceSelectionCommand.h
index 4173df556bbc9ea5d7d707f9bbc7c569135e2185..e4411ccd8f213bba9531554c476e8cade3c1f922 100644
--- a/Source/core/editing/ReplaceSelectionCommand.h
+++ b/Source/core/editing/ReplaceSelectionCommand.h
@@ -67,7 +67,7 @@ private:
 
         Node* firstNodeInserted() const { return m_firstNodeInserted.get(); }
         Node* lastLeafInserted() const { return m_lastNodeInserted ? &m_lastNodeInserted->lastDescendant() : 0; }
-        Node* pastLastLeaf() const { return m_lastNodeInserted ? NodeTraversal::next(*lastLeafInserted()) : 0; }
+        Node* pastLastLeaf() const { return m_lastNodeInserted ? NodeTraversal::next(m_lastNodeInserted->lastDescendant()) : 0; }
 
     private:
         RefPtr<Node> m_firstNodeInserted;