update-grub improperly inserting <cr> between devices on linux line of grub.cfg in multi-dev btrfs sys's

[DiagonalArg]

On a new install of wily. update-grub is improperly inserting a carriage return on the "linux" line of the grub.cfg menu items, between the two devices of a btrfs raid1 system (which for my system is in a luks container). The menu entries all looks like this:

menuentry 'Ubuntu' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-/dev/mapper/luks.root1_/dev/mapper/luks.root2' {
        recordfail
        load_video
        gfxmode $linux_gfx_mode
        insmod gzio
        if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
        insmod part_msdos
        insmod btrfs
        set root='hd2,msdos1'
        if [ x$feature_platform_search_hint = xy ]; then
          search --no-floppy --fs-uuid --set=root --hint-bios=hd2,msdos1 --hint-efi=hd2,msdos1 --hint-baremetal=ahci2,msdos1 fe74974e-3e23-43af-bfb1-7b520673c52b
        else
          search --no-floppy --fs-uuid --set=root <UUID>
        fi
        linux /@s3970boot/vmlinuz-4.2.0-23-generic root=/dev/mapper/luks.root1
/dev/mapper/luks.root2 ro rootflags=subvol=@ quiet splash $vt_handoff
        initrd /@s3970boot/initrd.img-4.2.0-23-generic
}

Removing that <cr> makes everything boot fine.
---
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CurrentDesktop: GNOME
DistroRelease: Ubuntu 15.10
InstallationDate: Installed on 2015-08-31 (130 days ago)
InstallationMedia: Ubuntu-GNOME 15.10 "Wily Werewolf" - Release amd64 (20151021)
Package: grub2 (not installed)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 4.2.0-23.28-generic 4.2.6
Tags: wily
Uname: Linux 4.2.0-23-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True

[DiagonalArg (diagonalarg)]

apport information

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.