Make VisiblePosition constructor private

Source/core/html/HTMLTextFormControlElementTest.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/html/HTMLTextFormControlElement.h"
 
 #include "core/dom/Text.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/Position.h"
@@ skipping 118 matching lines @@
     EXPECT_EQ(startLayoutCount, layoutCount());
     newCaretRect = LayoutRect(frameSelection.absoluteCaretBounds());
     EXPECT_NE(oldCaretRect, newCaretRect);
 }
 
 typedef Position (*PositionFunction)(const Position&);
 typedef VisiblePosition(*VisblePositionFunction)(const VisiblePosition&);
 
 void testFunctionEquivalence(const Position& position, PositionFunction positionFunction, VisblePositionFunction visibleFunction)
 {
-    VisiblePosition visiblePosition(position);
+    VisiblePosition visiblePosition = createVisiblePosition(position);
     VisiblePosition expected = visibleFunction(visiblePosition);
-    VisiblePosition actual = VisiblePosition(positionFunction(position));
+    VisiblePosition actual = createVisiblePosition(positionFunction(position));
     EXPECT_EQ(expected.deepEquivalent(), actual.deepEquivalent());
 }
 
 static VisiblePosition startOfWord(const VisiblePosition& position)
 {
     return startOfWord(position, LeftWordIfOnBoundary);
 }
 
 static VisiblePosition endOfWord(const VisiblePosition& position)
 {
@@ skipping 65 matching lines @@
     ASSERT_EQ(3, input->selectionStart());
 
     OwnPtrWillBePersistent<SpellChecker> spellChecker(SpellChecker::create(page().frame()));
     forceLayoutFlag();
     int startCount = layoutCount();
     spellChecker->respondToChangedSelection(oldSelection, FrameSelection::CloseTyping | FrameSelection::ClearTypingStyle);
     EXPECT_EQ(startCount, layoutCount());
 }
 
 } // namespace blink