Add error handling to visualization_manager.views.get_file_name()

[hackdna]

Commit: 561ef26

Steps to reproduce

Unknown (traceback received via email)

Observed behavior

Traceback (most recent call last):

  File "/srv/scc/virtualenvs/refinery-platform/lib/python2.7/site-packages/django/core/handlers/base.py", line 112, in get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)

  File "/srv/scc/apps/refinery-platform/refinery/core/views.py", line 714, in solr_igv
    session_urls = igv_multi_species(solr_results, solr_annot)

  File "/srv/scc/apps/refinery-platform/refinery/visualization_manager/views.py", line 200, in igv_multi_species
    sample_file = addIGVSamples(fields, unique_species[k]['solr'])

  File "/srv/scc/apps/refinery-platform/refinery/visualization_manager/views.py", line 456, in addIGVSamples
    pheno_results = get_sample_lines(fields_dict, results_samp)

  File "/srv/scc/apps/refinery-platform/refinery/visualization_manager/views.py", line 538, in get_sample_lines
    line, url = get_file_name(row["uuid"], sampFile=True)

  File "/srv/scc/apps/refinery-platform/refinery/visualization_manager/views.py", line 508, in get_file_name
    temp_fs = FileStoreItem.objects.get(uuid=curr_file_uuid)

  File "/srv/scc/virtualenvs/refinery-platform/lib/python2.7/site-packages/django/db/models/manager.py", line 151, in get
    return self.get_queryset().get(*args, **kwargs)

  File "/srv/scc/virtualenvs/refinery-platform/lib/python2.7/site-packages/django/db/models/query.py", line 310, in get
    self.model._meta.object_name)

DoesNotExist: FileStoreItem matching query does not exist.

Expected behavior

Error handled and an informative message presented to the user if necessary.