This was causing the following linker error on Microsoft Visual C++ when compiling as a DLL:

```
googletest-printers-test.cc.obj : error LNK2019: unresolved external symbol "void __cdecl testing::internal::PrintTo(char16_t const *,class std::basic_ostream<char,struct std::char_traits<char> > *)" (?PrintTo@internal@testing@@YAXPEB_SPEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@@Z) referenced in function "public: static void __cdecl testing::internal::UniversalPrinter<char16_t const *>::Print(char16_t const * const &,class std::basic_ostream<char,struct std::char_traits<char> > *)" (?Print@?$UniversalPrinter@PEB_S@internal@testing@@SAXAEBQEB_SPEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@@Z)
googletest-printers-test.cc.obj : error LNK2019: unresolved external symbol "void __cdecl testing::internal::PrintTo(char32_t const *,class std::basic_ostream<char,struct std::char_traits<char> > *)" (?PrintTo@internal@testing@@YAXPEB_UPEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@@Z) referenced in function "public: static void __cdecl testing::internal::UniversalPrinter<char32_t const *>::Print(char32_t const * const &,class std::basic_ostream<char,struct std::char_traits<char> > *)" (?Print@?$UniversalPrinter@PEB_U@internal@testing@@SAXAEBQEB_UPEAV?$basic_ostream@DU?$char_traits@D@std@@@std@@@Z)
```