Restore original 'Edit Result Columns' state on Cancel/Close action

Steps to reproduce on Nuxeo 7.10-HF10, 8.2 and nightly.nuxeo.com:

1. Select 'Edit Result Columns' action on folder/workspace
2. Move 'Description' item from Left column to Right column in FancyBox
3. Select 'Close' or 'Cancel' FancyBox action
Note: FancyBox closes as expected with folder/workspace content view unchanged
4. Again select 'Edit Result Columns' action on folder/workspace
Error: Description item remains in Right column in FancyBox (Step 3 should have restored the original state with 'Description' item back in the Left column)