message: shim some Windows functions
diff: @@ -623,11 +623,24 @@ impl<'a, 'mir, 'tcx: 'mir + 'a> EvalContextExt<'tcx> for EvalContext<'a, 'mir, '
  }
  // Windows API subs
  - "AddVectoredExceptionHandler" |
  - "SetThreadStackGuarantee" => {
  - let usize = self.tcx.types.usize;
  + "AddVectoredExceptionHandler" => {
  // any non zero value works for the stdlib. This is just used for stackoverflows anyway
  - self.write_scalar(dest, Scalar::from_u128(1), usize)?;
  + self.write_scalar(dest, Scalar::from_u128(1), dest_ty)?;
  + },
  + "GetModuleHandleW" |
  + "GetProcAddress" |
  + "InitializeCriticalSection" |
  + "EnterCriticalSection" |
  + "TryEnterCriticalSection" |
  + "LeaveCriticalSection" |
  + "DeleteCriticalSection" |
  + "SetLastError" => {
  + // pretend these do not exist/nothing happened, by returning zero
  + self.write_scalar(dest, Scalar::from_u128(0), dest_ty)?;
  + },
  + "GetLastError" => {
  + // this is c::ERROR_CALL_NOT_IMPLEMENTED
  + self.write_scalar(dest, Scalar::from_u128(120), dest_ty)?;
  },
  // We can't execute anything else
  