Cleanup LayoutTextControl and its subclasses.

Source/core/layout/LayoutTextControlMultiLine.cpp

 /**
  * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
  *           (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 30 matching lines @@
 {
     if (!LayoutTextControl::nodeAtPoint(result, locationInContainer, accumulatedOffset, hitTestAction))
         return false;
 
     if (result.innerNode() == node() || result.innerNode() == innerEditorElement())
         hitInnerEditorElement(result, locationInContainer.point(), accumulatedOffset);
 
     return true;
 }
 
-float LayoutTextControlMultiLine::getAvgCharWidth(AtomicString family)
+float LayoutTextControlMultiLine::getAvgCharWidth(const AtomicString& family) const
 {
     // Since Lucida Grande is the default font, we want this to match the width
     // of Courier New, the default font for textareas in IE, Firefox and Safari Win.
     // 1229 is the avgCharWidth value in the OS/2 table for Courier New.
     if (family == "Lucida Grande")
         return scaleEmToUnits(1229);
 
     return LayoutTextControl::getAvgCharWidth(family);
 }
 
@@ skipping 33 matching lines @@
         return placeholderLayoutObject;
     LayoutBox* placeholderBox = toLayoutBox(placeholderLayoutObject);
     placeholderBox->mutableStyleRef().setLogicalWidth(Length(contentLogicalWidth() - placeholderBox->borderAndPaddingLogicalWidth(), Fixed));
     placeholderBox->layoutIfNeeded();
     placeholderBox->setX(borderLeft() + paddingLeft());
     placeholderBox->setY(borderTop() + paddingTop());
     return placeholderLayoutObject;
 }
 
 }