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

core/fpdfdoc/cpdf_variabletext.cpp

Index: core/fpdfdoc/cpdf_variabletext.cpp
diff --git a/core/fpdfdoc/cpdf_variabletext.cpp b/core/fpdfdoc/cpdf_variabletext.cpp
index 040b7e60512546d2d8910d764b34a85640844496..12cf274321476ebba95840b5d61964653292f6b7 100644
--- a/core/fpdfdoc/cpdf_variabletext.cpp
+++ b/core/fpdfdoc/cpdf_variabletext.cpp
@@ -394,9 +394,8 @@ 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))