contrib/wix/defines.wxi

httppasswordmgrdbproxy: specify exact arguments

We only ever call these functions in a single way, so let's just
actually specify them. We need to do some string/bytes encoding
dancing here for Python 3, so it'll help to know what arguments we
need to convert.

# no-check-commit because I'm modifying functions that check-commit
does not like.

Differential Revision: https://phab.mercurial-scm.org/D885

<Include>

  <?if $(var.Platform) = "x64" ?>
    <?define IsX64 = yes ?>
  <?else?>
    <?define IsX64 = no ?>
  <?endif?>

</Include>