Replace calls to deprecated CFX_{Wide,Byte}String::Empty()

xfa/fde/tto/fde_textout.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/fde/tto/fde_textout.h"
 
 #include <algorithm>
 
@@ skipping 553 matching lines @@
   }
   if (rect.width < m_fFontSize || rect.height < m_fFontSize) {
     return;
   }
   FX_FLOAT fLineWidth = rect.width;
   if (m_dwStyles & FDE_TTOSTYLE_VerticalLayout) {
     fLineWidth = rect.height;
   }
   m_pTxtBreak->SetLineWidth(fLineWidth);
   m_ttoLines.RemoveAll(TRUE);
-  m_wsText.Empty();
+  m_wsText.clear();
   LoadText(pwsStr, iLength, rect);
   if (m_dwStyles & FDE_TTOSTYLE_Ellipsis) {
     ReplaceWidthEllipsis();
   }
   Reload(rect);
   DoAlignment(rect);
   OnDraw(rtClip);
 }
 void CFDE_TextOut::ExpandBuffer(int32_t iSize, int32_t iType) {
   switch (iType) {
@@ skipping 519 matching lines @@
     return NULL;
   }
   return m_pieces.GetPtrAt(index);
 }
 void CFDE_TTOLine::RemoveLast(int32_t iCount) {
   m_pieces.RemoveLast(iCount);
 }
 void CFDE_TTOLine::RemoveAll(FX_BOOL bLeaveMemory) {
   m_pieces.RemoveAll(bLeaveMemory);
 }