[core] Hue and Isilon issue "UnsupportedOperationException: Unknown op 'GETTRASHROOT'

Using the file browser in Hue with Isilon on CDH 5.12 is failing with the following error:

ERROR Potential detail: UnsupportedOperationException: Unknown op 'GETTRASHROOT' is not supported (error 400)
Processing exception: Cannot access: /user/lucky. Note: you are a Hue admin but not a HDFS superuser, "hdfs" or part of HDFS supergroup, "supergroup".
detail: UnsupportedOperationException: Unknown op 'GETTRASHROOT' is not supported (error 400).

Turns out our check for to see if "GETTRASHROOT" is a valid op doesn't work for Isilon. It only checks for "IllegalArgumentException", but it should also check for "UnsupportedOperationException".