Build error on Windows when using "int" for a file descriptor

There is a build error for mesos-tests in src/tests/check_tests.cpp on Windows associated with the use of an "int" file descriptor:

C:\mesos\mesos\src\tests\check_tests.cpp(1890): error C2440: 'initializing': cannot convert from 'Try<std::array<os::WindowsFD,2>,Error>' to 'Try<std::array<int,2>,Error>' [C:\mesos\mesos\build\src\tests\mesos-tests.vcxproj]