Stop converting widestring -> c_str -> widestring in several places.

core/fpdfdoc/cpdf_variabletext.cpp

 // Copyright 2016 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 "core/fpdfdoc/include/cpdf_variabletext.h"
 
 #include "core/fpdfapi/fpdf_font/include/cpdf_font.h"
 #include "core/fpdfdoc/cpvt_wordinfo.h"
@@ skipping 376 matching lines @@
 }
 
 CPVT_WordPlace CPDF_VariableText::DeleteWord(const CPVT_WordPlace& place) {
   return ClearRightWord(AdjustLineHeader(place, TRUE));
 }
 
 CPVT_WordPlace CPDF_VariableText::BackSpaceWord(const CPVT_WordPlace& place) {
   return ClearLeftWord(AdjustLineHeader(place, TRUE));
 }
 
-void CPDF_VariableText::SetText(const FX_WCHAR* text) {
+void CPDF_VariableText::SetText(const CFX_WideString& swText) {
   DeleteWords(CPVT_WordRange(GetBeginWordPlace(), GetEndWordPlace()));
-  CFX_WideString swText = text;
   CPVT_WordPlace wp(0, 0, -1);
   CPVT_SectionInfo secinfo;
   if (CSection* pSection = m_SectionArray.GetAt(0))
     pSection->m_SecInfo = secinfo;
 
   int32_t nCharCount = 0;
   for (int32_t i = 0, sz = swText.GetLength(); i < sz; i++) {
     if (m_nLimitChar > 0 && nCharCount >= m_nLimitChar)
       break;
     if (m_nCharArray > 0 && nCharCount >= m_nCharArray)
@@ skipping 727 matching lines @@
                        ptLeftTop.y);
 }
 
 CPVT_FloatRect CPDF_VariableText::OutToIn(const CFX_FloatRect& rect) const {
   CFX_FloatPoint ptLeftTop = OutToIn(CFX_FloatPoint(rect.left, rect.top));
   CFX_FloatPoint ptRightBottom =
       OutToIn(CFX_FloatPoint(rect.right, rect.bottom));
   return CPVT_FloatRect(ptLeftTop.x, ptLeftTop.y, ptRightBottom.x,
                         ptRightBottom.y);
 }