bzr crashed with MalformedTransform in resolve_conflicts(): Tree transform is malformed [('versioning no contents', 'new-119')]

[Clint Byrum]

Simple to reproduce:

mkdir /tmp/test
cd /tmp/test
bzr init-repo bzr
cd bzr
bzr branch ubuntu:autofs5
cd autofs5
bzr update -r 17

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: bzr 2.5.0-1ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-18.28-generic 3.2.9
Uname: Linux 3.2.0-18-generic x86_64
NonfreeKernelModules: nvidia wl
ApportVersion: 1.94.1-0ubuntu1
Architecture: amd64
BzrDebugFlags: set()
BzrVersion: 2.5.0
CommandLine: ['/usr/bin/bzr', 'update', '-r', '17']
CrashDb: bzr
Date: Fri Mar 9 16:59:49 2012
ExecutablePath: /usr/bin/bzr
FileSystemEncoding: UTF-8
InstallationMedia: Xubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101008.1)
InterpreterPath: /usr/bin/python2.7
Locale: en_US.UTF-8
PackageArchitecture: all
Platform: Linux-3.2.0-18-generic-x86_64-with-Ubuntu-12.04-precise
ProcCmdline: /usr/bin/python /usr/bin/bzr update -r 17
ProcEnviron:
 SHELL=/bin/bash
 TERM=xterm
 PATH=(custom, user)
 LANG=en_US.UTF-8
PythonVersion: 2.7.2
SourcePackage: bzr
Title: bzr crashed with MalformedTransform in resolve_conflicts(): Tree transform is malformed [('versioning no contents', 'new-119')]
UpgradeStatus: Upgraded to precise on 2011-07-14 (239 days ago)
UserEncoding: utf-8
UserGroups: adm admin cdrom dialout libvirtd lpadmin plugdev sambashare sbuild

[Launchpad Janitor (janitor)]

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