Don't allow "Hide Closed" to bleed into dashboard datagrids.

The toggle for hiding closed review requests on the user and all review request
grids would set a profile flag, and then bled into the "All Outgoing" datagrid.
This change adds some plumbing to prevent this from happening.

Testing done:
Reproduced the bug, and then tried with this change. Saw that with the profile
flag set, the dashboard datagrids showed closed review requests, but the others
did not.

Fixes bug 3319.

Reviewed at https://reviews.reviewboard.org/r/5746/