Data role editor modifications can result in duplicate roles being generated.

Reproduction seems inconsistent, but the below steps have produced an issue more than once. The issue also appears to present different dependent upon the method of opening the data role to edit (double-click versus using the "Edit selected data role" icon). Steps to replicate: 1) create a new role (for example, "testRole") 2) click finish to save the role 3) edit the role to adjust permissions (for instance, remove read permissions from a table) 4) click finish to save the modified role 5) adjust model in vdb (for instance renaming a child table) 6) save model 7) synchronize vdb 8) edit the role to verify permissions (in testing this showed the correct permissions) and click cancel if correct 9) edit the role to verify permissions again (this showed different permissions than step 8 in multiple tests)