Description of problem:
When hitting the Clusters tab under any Data Center ('Compute > Data Centers'), the clusters list loading is stuck and kind of error appears on the engine.log


Version-Release number of selected component (if applicable):
- ovirt-engine-4.4.0-0.14.master.el7.noarch
- ovirt-web-ui-1.6.0-2.el7ev.noarch
- ovirt-engine-ui-extensions-1.0.10-1.el7ev.noarch


How reproducible:
100%

Steps to Reproduce:
1. On the web-ui go to 'Compute > Data Centers'
2. Hit the Clusters tab.

Actual results:
Clusters list loading is stuck, and the following line will appear on the engine.log

2020-01-22 16:50:08,125+02 INFO  [org.ovirt.engine.core.bll.SearchQuery] (default task-25) [84fb8819-4af6-401e-ab4b-516cfb8e6a50] ResourceManager::searchBusinessObjects - erroneous search text - ''clusters: datacenter.name=golden_env_mixed'' error - ''clusters: datacenter$n$ame=golden_env_mixed''


Expected results:
Clusters list will be loaded

Additional info:
- No change even after a few minutes I wait for the clusters list.
- The list under 'Compute > Clusters' works as expected.