Make VisiblePosition constructor private

Source/core/editing/iterators/TextIterator.cpp

Index: Source/core/editing/iterators/TextIterator.cpp
diff --git a/Source/core/editing/iterators/TextIterator.cpp b/Source/core/editing/iterators/TextIterator.cpp
index 017f40923f6673800e119b81a2df474b6d0d0404..c0bd614b8a7901707db2e64fdb84caeddea766f7 100644
--- a/Source/core/editing/iterators/TextIterator.cpp
+++ b/Source/core/editing/iterators/TextIterator.cpp
@@ -881,8 +881,8 @@ bool TextIteratorAlgorithm<Strategy>::shouldRepresentNodeOffsetZero()
     // and in that case we'll get null. We don't want to put in newlines at the start in that case.
     // The currPos.isNotNull() check is needed because positions in non-HTML content
     // (like SVG) do not have visible positions, and we don't want to emit for them either.
-    VisiblePosition startPos = VisiblePosition(Position(m_startContainer, m_startOffset));
-    VisiblePosition currPos = VisiblePosition(positionBeforeNode(m_node));
+    VisiblePosition startPos = createVisiblePosition(Position(m_startContainer, m_startOffset));
+    VisiblePosition currPos = createVisiblePosition(positionBeforeNode(m_node));
     return startPos.isNotNull() && currPos.isNotNull() && !inSameLine(startPos, currPos);
 }