Some shell jobs are causing Checkbox Converged to crash

Example, running graphics/xorg-version

INFO:checkbox.touch.qml:invoking get_next_test on object created withcheckbox_touch.create_app_object, with args: [] ...
INFO:checkbox.touch.qml:get_next_test on object created withcheckbox_touch.create_app_object, with args: [] returned: {"code":200,"result":{"command":"xdpyinfo | grep \"^X.Org version\" | cut -d ':' -f 2 | tr -d ' '","description":"Test to output the Xorg version","flags":[],"id":"2013.com.canonical.certification::graphics/xorg-version","name":"Test Xorg version","partial_id":"graphics/xorg-version","plugin":"shell","start_time":1441023126.8001122,"test_number":1,"tests_count":3,"verificationDescription":"Test to output the Xorg version"}}
INFO:checkbox.touch.qml:invoking run_test_activity on object created withcheckbox_touch.create_app_object, with args: [{"command":"xdpyinfo | grep \"^X.Org version\" | cut -d ':' -f 2 | tr -d ' '","description":"Test to output the Xorg version","flags":[],"id":"2013.com.canonical.certification::graphics/xorg-version","name":"Test Xorg version","partial_id":"graphics/xorg-version","plugin":"shell","start_time":1441023126.8001122,"test_number":1,"tests_count":3,"verificationDescription":"Test to output the Xorg version"}] ...
INFO:plainbox.runner:Running <JobDefinition id:'2013.com.canonical.certification::graphics/xorg-version' plugin:'shell'>
ERROR:checkbox.touch:run_test_activity(...) raised TypeError('no such field: comment',)
Traceback (most recent call last):
  File "/usr/share/checkbox-converged/py/checkbox_touch.py", line 524, in run_test_activity
    result = self.runner.run_job(job, job_state, self.config, self.ui)
  File "/usr/lib/python3/dist-packages/plainbox/impl/runner.py", line 434, in run_job
    return runner(job, job_state, config)
  File "/usr/lib/python3/dist-packages/plainbox/impl/runner.py", line 460, in run_shell_job
    return self._just_run_command(job, job_state, config).get_result()
  File "/usr/lib/python3/dist-packages/plainbox/impl/runner.py", line 801, in _just_run_command
    job, job_state, config, ctrl)
  File "/usr/lib/python3/dist-packages/plainbox/impl/runner.py", line 903, in _run_command
    job, job_state, config, extcmd_popen, ctrl)
  File "/usr/lib/python3/dist-packages/plainbox/impl/runner.py", line 914, in _run_extcmd
    extcmd_popen)
  File "/usr/lib/python3/dist-packages/plainbox/impl/ctrl.py", line 538, in execute_job
    return_code = extcmd_popen.call(cmd, env=env, cwd=cwd_dir)
  File "/usr/lib/python3/dist-packages/plainbox/vendor/extcmd/__init__.py", line 493, in call
    proc = self._popen(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/plainbox/vendor/extcmd/__init__.py", line 276, in _popen
    return subprocess.Popen(*args, **kwargs)
  File "/usr/lib/python3.4/subprocess.py", line 848, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.4/subprocess.py", line 1384, in _execute_child
    restore_signals, start_new_session, preexec_fn)
OSError: [Errno 12] Cannot allocate memory

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/share/checkbox-converged/py/checkbox_touch.py", line 110, in wrapper
    result = func(*args, **kwargs)
  File "/usr/share/checkbox-converged/py/checkbox_touch.py", line 529, in run_test_activity
    ).get_result()
  File "/usr/lib/python3/dist-packages/plainbox/impl/pod.py", line 405, in __init__
    raise TypeError("no such field: {}".format(field_name))
TypeError: no such field: comment
INFO:checkbox.touch.qml:run_test_activity on object created withcheckbox_touch.create_app_object, with args: [{"command":"xdpyinfo | grep \"^X.Org version\" | cut -d ':' -f 2 | tr -d ' '","description":"Test to output the Xorg version","flags":[],"id":"2013.com.canonical.certification::graphics/xorg-version","name":"Test Xorg version","partial_id":"graphics/xorg-version","plugin":"shell","start_time":1441023126.8001122,"test_number":1,"tests_count":3,"verificationDescription":"Test to output the Xorg version"}] returned: {"code":500,"error":"no such field: comment","traceback":"Traceback (most recent call last):\n File \"/usr/share/checkbox-converged/py/checkbox_touch.py\", line 524, in run_test_activity\n result = self.runner.run_job(job, job_state, self.config, self.ui)\n File \"/usr/lib/python3/dist-packages/plainbox/impl/runner.py\", line 434, in run_job\n return runner(job, job_state, config)\n File \"/usr/lib/python3/dist-packages/plainbox/impl/runner.py\", line 460, in run_shell_job\n return self._just_run_command(job, job_state, config).get_result()\n File \"/usr/lib/python3/dist-packages/plainbox/impl/runner.py\", line 801, in _just_run_command\n job, job_state, config, ctrl)\n File \"/usr/lib/python3/dist-packages/plainbox/impl/runner.py\", line 903, in _run_command\n job, job_state, config, extcmd_popen, ctrl)\n File \"/usr/lib/python3/dist-packages/plainbox/impl/runner.py\", line 914, in _run_extcmd\n extcmd_popen)\n File \"/usr/lib/python3/dist-packages/plainbox/impl/ctrl.py\", line 538, in execute_job\n return_code = extcmd_popen.call(cmd, env=env, cwd=cwd_dir)\n File \"/usr/lib/python3/dist-packages/plainbox/vendor/extcmd/__init__.py\", line 493, in call\n proc = self._popen(*args, **kwargs)\n File \"/usr/lib/python3/dist-packages/plainbox/vendor/extcmd/__init__.py\", line 276, in _popen\n return subprocess.Popen(*args, **kwargs)\n File \"/usr/lib/python3.4/subprocess.py\", line 848, in __init__\n restore_signals, start_new_session)\n File \"/usr/lib/python3.4/subprocess.py\", line 1384, in _execute_child\n restore_signals, start_new_session, preexec_fn)\nOSError: [Errno 12] Cannot allocate memory\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n File \"/usr/share/checkbox-converged/py/checkbox_touch.py\", line 110, in wrapper\n result = func(*args, **kwargs)\n File \"/usr/share/checkbox-converged/py/checkbox_touch.py\", line 529, in run_test_activity\n ).get_result()\n File \"/usr/lib/python3/dist-packages/plainbox/impl/pod.py\", line 405, in __init__\n raise TypeError(\"no such field: {}\".format(field_name))\nTypeError: no such field: comment\n"}
ERROR:checkbox.touch.qml:Unable to run test activity
Stacktrace:
#0 @file:///usr/share/checkbox-converged/components/PythonLogger.qml:91
#1 @file:///usr/share/checkbox-converged/components/CheckboxTouchApplication.qml:141
#2 @file:///usr/share/checkbox-converged/components/CheckboxTouchApplication.qml:182
#3 @file:///usr/share/checkbox-converged/components/PythonObjectRef.qml:68