Move computeInlineBoxPosition() out from VisiblePosition

Source/core/editing/FrameSelection.cpp

 /*
  * Copyright (C) 2004, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 510 matching lines @@
 
 TextDirection FrameSelection::directionOfSelection()
 {
     InlineBox* startBox = nullptr;
     InlineBox* endBox = nullptr;
     // Cache the VisiblePositions because visibleStart() and visibleEnd()
     // can cause layout, which has the potential to invalidate lineboxes.
     VisiblePosition startPosition = m_selection.visibleStart();
     VisiblePosition endPosition = m_selection.visibleEnd();
     if (startPosition.isNotNull())
-        startBox = startPosition.computeInlineBoxPosition().inlineBox;
+        startBox = computeInlineBoxPosition(startPosition).inlineBox;
     if (endPosition.isNotNull())
-        endBox = endPosition.computeInlineBoxPosition().inlineBox;
+        endBox = computeInlineBoxPosition(endPosition).inlineBox;
     if (startBox && endBox && startBox->direction() == endBox->direction())
         return startBox->direction();
 
     return directionOfEnclosingBlock();
 }
 
 void FrameSelection::didChangeFocus()
 {
     // Hits in virtual/gpu/compositedscrolling/scrollbars/scrollbar-miss-mousemove-disabled.html
     DisableCompositingQueryAsserts disabler;
@@ skipping 1513 matching lines @@
 
 void showTree(const blink::FrameSelection* sel)
 {
     if (sel)
         sel->showTreeForThis();
     else
         fprintf(stderr, "Cannot showTree for (nil) FrameSelection.\n");
 }
 
 #endif