use UTF8-encoded char* strings in UTF8 build instead of wchar_t* if the current locale uses UTF8;

fall back to widechar CRT functions in the locale is not UTF8


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45663 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/stringimpl.cpp

@@ -752,7 +752,6 @@ bool wxStringImpl::ConcatSelf(size_t nSrcLen,
   return true;
 }
 
-#if !wxUSE_UNICODE_UTF8
 // get the pointer to writable buffer of (at least) nLen bytes
 wxStringCharType *wxStringImpl::DoGetWriteBuf(size_t nLen)
 {
@@ -784,6 +783,5 @@ void wxStringImpl::DoUngetWriteBuf(size_t nLen)
   pData->nDataLength = nLen;
   pData->Validate(true);
 }
-#endif // !wxUSE_UNICODE_UTF8
 
 #endif // !wxUSE_STL_BASED_WXSTRING