Bug 7206

To reproduce:

1. Run a failed build with Toaster
2. In the all builds page, click on the download icon that shows next to the number of errors

This should download the build cooker log, but instead throws this error

Environment:


Request Method: GET
Request URL: http://127.0.0.1:8000/toastergui/build/3/artifact/cookerlog/id/3

Django Version: 1.6
Python Version: 2.7.6
Installed Applications:
('django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.messages',
'django.contrib.sessions',
'django.contrib.admin',
'django.contrib.staticfiles',
'django.contrib.humanize',
'orm',
'toastermain',
'south',
'bldviewer',
'toastergui',
'bldcontrol')
Installed Middleware:
('django.middleware.common.CommonMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware')


Traceback:
File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py"
in get_response
  114.                     response = wrapped_callback(request,
*callback_args, **callback_kwargs)
File "/home/yocto/master/bitbake/lib/toaster/toastergui/views.py" in
build_artifact
  2939.             fsock = b.buildrequest.environment.get_artifact(file_name)
File "/home/yocto/master/bitbake/lib/toaster/bldcontrol/models.py" in
get_artifact
  78.             return open(path, "r")

Exception Type: IOError at /toastergui/build/3/artifact/cookerlog/id/3
Exception Value: [Errno 2] No such file or directory:
u'/home/yocto/master/build/tmp/log/cooker/qemux86/20150120180920.log'