BUG: change user select box failed while changing user.

[atarkowska]

In collaborative mode when switching between users following error is generated. It require dipper investigation because group select box works fine.

Environment:


Request Method: GET
Request URL: http://localhost:4080/webclient/userdata/?experimenter=8

Django Version: 1.3.1
Python Version: 2.6.6
Installed Applications:
['django.contrib.staticfiles',
 'django.contrib.markup',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.sites',
 'omeroweb.feedback',
 'omeroweb.webadmin',
 'omeroweb.webclient',
 'omeroweb.webgateway',
 'omeroweb.webtest',
 'omeroweb.webmobile',
 'omeroweb.webpublic',
 'omeroweb.webredirect',
 'omeroweb.common']
Installed Middleware:
('django.middleware.common.CommonMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware')


Traceback:
File "/Users/ola/Dev/omero/dist/lib/python/django/core/handlers/base.py" in get_response
  111.                         response = callback(request, *callback_args, **callback_kwargs)
File "/Users/ola/Dev/omero/components/tools/OmeroWeb/omeroweb/../omeroweb/webclient/views.py" in wrapped
  174.         return f(request, *args, **kwargs)
File "/Users/ola/Dev/omero/components/tools/OmeroWeb/omeroweb/../omeroweb/webclient/views.py" in load_template
  507.             if form_users.is_valid():
File "/Users/ola/Dev/omero/dist/lib/python/django/forms/forms.py" in is_valid
  121.         return self.is_bound and not bool(self.errors)
File "/Users/ola/Dev/omero/dist/lib/python/django/forms/forms.py" in _get_errors
  112.             self.full_clean()
File "/Users/ola/Dev/omero/dist/lib/python/django/forms/forms.py" in full_clean
  267.         self._clean_fields()
File "/Users/ola/Dev/omero/dist/lib/python/django/forms/forms.py" in _clean_fields
  284.                     value = field.clean(value)
File "/Users/ola/Dev/omero/components/tools/OmeroWeb/omeroweb/../omeroweb/webadmin/custom_forms.py" in clean
  283.         Field.clean(self, value)
File "/Users/ola/Dev/omero/dist/lib/python/django/forms/fields.py" in clean
  163.         value = self.to_python(value)
File "/Users/ola/Dev/omero/dist/lib/python/django/forms/models.py" in to_python
  973.         except (ValueError, self.queryset.model.DoesNotExist):

Exception Type: AttributeError at /webclient/userdata/
Exception Value: 'list' object has no attribute 'model'

[jburel]

Moved from sprint 2011-12-13 (4)

[wmoore]

See #7692. I committed a fix for this. Just needs reviewing.