Add a workaround for failed assertion in VS debugger

Assertion failed: ploc->_Mbcurmax == 1 || ploc->_Mbcurmax == 2

Apparently MS C/C++ library doesn't support UTF-8 locales, which causes the assertion to fail. My solution is to ignore the system locale and try to set the classic one.

LibreOffice seems to have this problem fixed in less simple way: https://gerrit.libreoffice.org/#/c/54110/

src/app/app.cpp

@@ -1832,7 +1832,12 @@ void CApplication::SetLanguage(Language language)
     // Update C++ locale
     try
     {
+#if defined(_MSC_VER) && defined(_DEBUG)
+        // Avoids failed assertion in VS debugger
+        throw -1;
+#else
         std::locale::global(std::locale(systemLocale.c_str()));
+#endif
     }
     catch (...)
     {