While building images in a dual boot host, /dev/sda is leaking into build's grub config. It is visible in the logs that the commands GRUB-INSTALL and GRUB-MKCONFIG probes Host OS environment. This is avoided by setting grub_disable_os_prober to true in /default/grub config file. Change-Id: I7408de7b3bc8a62f8bf103f00a88a596f988353c Closes-Bug: 1166491
Sets up a partitioned disk (rather than building just one filesystem with no partition table).
By default the disk will have grub[2]-install run on it. In case GRUB2 is not available in the system, a fallback to Extlinux will happen. It's also possible to enforce the use of Extlinux by exporting a DIB_EXTLINUX variable to the environment.