A challenge for getting LibTest working on Windows has always
been CrashTest. It implements death tests similar to Google Test
where a child process is cloned to invoke the expression that
should abort/terminate the program. Then the exit code of the
child is used by the parent test process to verify if the
application correctly aborted/terminated due to invoking
the expression.
The problem was that finding an equivalent way to port Crash::run()
to Windows was not looking very likely as publicly exposed Win32/
Native APIs have no equivalent to fork(); however, Windows actually
does have native support for process cloning via undocumented NT
APIs that clever people reverse engineered and published, see
`NtCreateUserProcess()`.
All that being said, this `EXPECT_DEATH()` implementation avoids
needing to use a child process in general, allowing us to remove
CrashTest in favour of a single cross-platform solution for death
tests.
