Question on how to ITP package not in debian but in other variant for years

[Roger Shimizu <rogershimizu@gmail.com>]

Dear Mentors,

I'm going to ITP a package not in debian but already in other Debian
based distro for years. From technical side, I think it's kinda like
ITA, because all Debian packaging related stuff is already there.

Since I didn't find any document describing how to do with this kind
of case, I want to confirm here before starting.

Here's some questions I have:
- I usually use git/gbp to packaging. Do I need to keep history of
original debian related stuff (debian/ directory)?
- Do I need to ask upstream (Debian based distro) packaging
maintainer? or it's better to encourage them to ITP? (upstream package
already existed for years, so I think they might be not interested in
it)

And here's the package I'm going to ITP:
  code upstream: https://github.com/JesusFreke/smali
  pkg upstream: http://git.kali.org/gitweb/?p=packages/smali.git or
git://git.kali.org/packages/smali.git
  License: BSD-3-clause / Apache-2.0

Thank you and look forward to your reply!

Cheers,
Roger