grub-xen-host binary package in Ubuntu Oracular amd64

 GRUB is a portable, powerful bootloader. This version of GRUB is based on a
 cleaner design than its predecessors, and provides the following new features:
 .
  - Scripting in grub.cfg using BASH-like syntax.
  - Support for modern partition maps such as GPT.
  - Modular generation of grub.cfg via update-grub. Packages providing GRUB
    add-ons can plug in their own script rules and trigger updates by invoking
    update-grub.
 .
 This package arranges for GRUB binary images which can be used to boot a Xen
 guest (i.e. PV-GRUB) to be present in the control domain filesystem.

Source package