Description of problem:
-----------------------
The UI blows up with this error while drilling into host C&U graphs.

Error text:
undefined method `downcase' for nil:NilClass [vm/show_list]

Snippet from production.log:
tZSI6IkRpc3BsYXktVk1zLW9uIn0=", "sb_controller"=>"host"}
[----] F, [2016-11-08T15:30:22.063225 #3264:1232a84] FATAL -- : Error caught: [NoMethodError] undefined method `downcase' for nil:NilClass
/var/www/miq/vmdb/app/controllers/application_controller.rb:1643:in `get_view_where_clause'
/var/www/miq/vmdb/app/controllers/application_controller.rb:1595:in `get_view'
/var/www/miq/vmdb/app/controllers/application_controller/ci_processing.rb:1616:in `process_show_list'
/var/www/miq/vmdb/app/controllers/vm_controller.rb:16:in `show_list'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal/basic_implicit_render.rb:4:in `send_action'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/abstract_controller/base.rb:188:in `process_action'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal/rendering.rb:30:in `process_action'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/abstract_controller/callbacks.rb:20:in `block in process_action'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:126:in `call'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:506:in `block (2 levels) in compile'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:455:in `call'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:101:in `__run_callbacks__'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:750:in `_run_process_action_callbacks'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:90:in `run_callbacks'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/abstract_controller/callbacks.rb:19:in `process_action'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal/rescue.rb:20:in `process_action'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/notifications.rb:164:in `block in instrument'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/notifications/instrumenter.rb:21:in `instrument'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/notifications.rb:164:in `instrument'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal/params_wrapper.rb:248:in `process_action'
/opt/rh/cfme-gemset/gems/activerecord-5.0.0.1/lib/active_record/railties/controller_runtime.rb:18:in `process_action'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/abstract_controller/base.rb:126:in `process'
/opt/rh/cfme-gemset/gems/actionview-5.0.0.1/lib/action_view/rendering.rb:30:in `process'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal.rb:190:in `dispatch'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_controller/metal.rb:262:in `dispatch'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/routing/route_set.rb:50:in `dispatch'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/routing/route_set.rb:32:in `serve'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/journey/router.rb:39:in `block in serve'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/journey/router.rb:26:in `each'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/journey/router.rb:26:in `serve'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/routing/route_set.rb:725:in `call'
/opt/rh/cfme-gemset/gems/secure_headers-3.0.3/lib/secure_headers/middleware.rb:10:in `call'
/opt/rh/cfme-gemset/gems/rack-2.0.1/lib/rack/etag.rb:25:in `call'
/opt/rh/cfme-gemset/gems/rack-2.0.1/lib/rack/conditional_get.rb:25:in `call'
/opt/rh/cfme-gemset/gems/rack-2.0.1/lib/rack/head.rb:12:in `call'
/opt/rh/cfme-gemset/gems/rack-2.0.1/lib/rack/session/abstract/id.rb:222:in `context'
/opt/rh/cfme-gemset/gems/rack-2.0.1/lib/rack/session/abstract/id.rb:216:in `call'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/middleware/cookies.rb:613:in `call'
/opt/rh/cfme-gemset/gems/actionpack-5.0.0.1/lib/action_dispatch/middleware/callbacks.rb:38:in `block in call'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:97:in `__run_callbacks__'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:750:in `_run_call_callbacks'
/opt/rh/cfme-gemset/gems/activesupport-5.0.0.1/lib/active_support/callbacks.rb:90:in `run_callbacks'



Version-Release number of selected component (if applicable):
--------------------------------
5.7.0.9


How reproducible:
----------------
Always


Steps to Reproduce:
-------------------
1.Manage an infra provider.Enable C&U collection for the provider.
2.From the summary page of any host, click 'Monitoring', then click 'Utilization'.
3.Drill into the C&U graphs by left clicking any of the data points.
Eg: Click 'Display', click 'VMs that were running'.


Actual results:
--------------
UI error


Expected results:
-----------------
no UI error


Additional info:
----------------