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

fpdfsdk/pdfwindow/PWL_Utils.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 "fpdfsdk/pdfwindow/PWL_Utils.h"
 
 #include <algorithm>
 
@@ skipping 430 matching lines @@
   pEdit->SetAlignmentH(nAlignmentH, TRUE);
   pEdit->SetAlignmentV(nAlignmentV, TRUE);
   pEdit->SetMultiLine(bMultiLine, TRUE);
   pEdit->SetAutoReturn(bAutoReturn, TRUE);
   if (IsFloatZero(fFontSize))
     pEdit->SetAutoFontSize(TRUE, TRUE);
   else
     pEdit->SetFontSize(fFontSize);
 
   pEdit->Initialize();
-  pEdit->SetText(sText.c_str());
+  pEdit->SetText(sText);
 
   CFX_ByteString sEdit =
       CPWL_Utils::GetEditAppStream(pEdit.get(), CFX_FloatPoint(0.0f, 0.0f));
   if (sEdit.GetLength() > 0)
     sRet << "BT\n" << CPWL_Utils::GetColorAppStream(crText) << sEdit << "ET\n";
 
   return sRet.MakeString();
 }
 
 CFX_ByteString CPWL_Utils::GetPushButtonAppStream(const CFX_FloatRect& rcBBox,
@@ skipping 11 matching lines @@
   pEdit->SetAlignmentH(1, TRUE);
   pEdit->SetAlignmentV(1, TRUE);
   pEdit->SetMultiLine(FALSE, TRUE);
   pEdit->SetAutoReturn(FALSE, TRUE);
   if (IsFloatZero(fFontSize))
     pEdit->SetAutoFontSize(TRUE, TRUE);
   else
     pEdit->SetFontSize(fFontSize);
 
   pEdit->Initialize();
-  pEdit->SetText(sLabel.c_str());
+  pEdit->SetText(sLabel);
 
   CFX_FloatRect rcLabelContent = pEdit->GetContentRect();
   CPWL_Icon Icon;
   PWL_CREATEPARAM cp;
   cp.dwFlags = PWS_VISIBLE;
   Icon.Create(cp);
   Icon.SetIconFit(&IconFit);
   Icon.SetPDFStream(pIconStream);
 
   CFX_FloatRect rcLabel = CFX_FloatRect(0, 0, 0, 0);
@@ skipping 2851 matching lines @@
           break;
         case COLORTYPE_RGB:
           CPWL_Utils::ConvertCMYK2RGB(fColor1, fColor2, fColor3, fColor4,
                                       fColor1, fColor2, fColor3);
           break;
       }
       break;
   }
   nColorType = nConvertColorType;
 }