Could not resolve rosdep key 'message_generation'

edit

When I try to release a simple message package to Hydro, it fails:

$ git-bloom-release hydro
Processing release track settings for 'hydro'
Checking upstream devel branch for a package.xml(s) or stack.xml
Looking for packages in 'master' branch... found 'ackermann_msgs'.
Detected version '0.9.0' from package(s): ['ackermann_msgs']

Executing release track 'hydro'
==> bloom-export-upstream /tmp/tmp_wXBdW git --tag 0.9.0 --display-uri https://github.com/jack-oquin/ackermann_msgs.git --name ackermann_msgs --output-dir /tmp/tmpIuNRNs
Checking out repository at 'https://github.com/jack-oquin/ackermann_msgs.git' to reference '0.9.0'.
Exporting to archive: '/tmp/tmpIuNRNs/ackermann_msgs-0.9.0.tar.gz'
md5: 9a3ea71412a579bcf13b65039c1f8a08

==> git-bloom-import-upstream /tmp/tmpIuNRNs/ackermann_msgs-0.9.0.tar.gz  --release-version 0.9.0 --replace
The latest upstream tag in the release repository is 'upstream/0.9.0'.
Removing tag: 'upstream/0.9.0'
Importing archive into upstream branch...
Creating tag: 'upstream/0.9.0'
I'm happy.  You should be too.

==> git-bloom-generate -y rosrelease hydro --source upstream -i 0
Releasing package: ['ackermann_msgs']
Releasing package 'ackermann_msgs' for 'hydro' to: 'release/hydro/ackermann_msgs'

==> git-bloom-generate -y rosdebian --prefix release/hydro hydro -i 0
Generating source debs for the packages: ['ackermann_msgs']
Debian Incremental Version: 0
Debian Distributions: ['precise', 'quantal', 'raring']
Releasing for rosdistro: hydro
Running 'rosdep update'...

####
#### Generating 'precise' debian for package 'ackermann_msgs' at version '0.9.0-0'
####
Generating debian for precise...
Could not resolve rosdep key 'message_generation'
Resolve problem with rosdep and then continue to try again.
Continue [Y/n]? 
Running 'rosdep update'...
Could not resolve rosdep key 'message_generation'
Resolve problem with rosdep and then continue to try again.
Continue [Y/n]? n
Traceback (most recent call last):
  File "/usr/bin/git-bloom-generate", line 9, in <module>
    load_entry_point('bloom==0.3.2', 'console_scripts', 'git-bloom-generate')()
  File "/usr/lib/pymodules/python2.7/bloom/commands/git/generate.py", line 237, in main
    run_generator(generator, args)
  File "/usr/lib/pymodules/python2.7/bloom/commands/git/generate.py", line 160, in run_generator
    gen.post_rebase, destination)
  File "/usr/lib/pymodules/python2.7/bloom/commands/git/generate.py", line 99, in try_execute
    retcode = func(*args, **kwargs)
  File "/usr/lib/pymodules/python2.7/bloom/generators/debian/generator.py", line 225, in post_rebase
    self.generate_debian(data, stamp, distro)
  File "/usr/lib/pymodules/python2.7/bloom/generators/debian/generator.py", line 366, in generate_debian
    self.resolved_dependencies = self.resolve_dependencies(self.depends + self.build_depends, debian_distro)
  File "/usr/lib/pymodules/python2.7/bloom/generators/debian/generator.py", line 485, in resolve_dependencies
    resolved_depends[rosdep_key] = resolve_rosdep_key(rosdep_key, rosdep_view)
  File "/usr/lib/pymodules/python2.7/bloom/generators/debian/generator.py", line 479, in resolve_rosdep_key
    return resolve_rosdep_key(rosdep_key, new_view)
  File "/usr/lib/pymodules/python2.7/bloom/generators/debian/generator.py", line 481, in resolve_rosdep_key
    .format(rosdep_key))
  File "/usr/lib/pymodules/python2.7/bloom/generators/common.py", line 73, in exit
    raise GeneratorError(retcode)
GeneratorError: Error running generator

<== Error running command 'git-bloom-generate -y rosdebian --prefix release/hydro hydro -i 0'

On my system, the message_generation key is defined for precise and quantal, but not for raring:

$ rosdep resolve message_generation --os=ubuntu:raring

ERROR: No definition of [message_generation] for OS version [raring]

No ...