Filter merge requests by participant (team)

Description

We are using GitLab EE at work for the management of different projects owned by different groups. Each developer is member of multiple groups.

As we are using merge requests with minimum approvals, we work hard to do those code reviews quickly. In order to do so, we are looking for a way to see a list of all merge requests we participate in. I.e. for example I would like to fiter the list of merge requests under dashboard/merge_requests by "Participant" and would like to see all requests I am a participant of.

This will enable me to quickly go through all of them and have a great overview on what's on the plate to be done.

Proposal

Please add a new filter to dashboard/merge_requests enabling the user to filter by participant.

Overview

What is it? - A new filter to see a list of all merge requests one participates in.

Why should someone use this feature? - This will enable the users to have a much better overview on the merge requests they are still supposed to go through.

What is the underlying (business) problem? - It takes long and needs much more attention to look through all projects one is a member of to see all merge requests one has to do. E.g. for me it keeps happening that I go to the first team / group in my list, look for merge requests (in that group) and do the first of those requests. Then, when I click on merge requests up top, it brings me back to the requests of this project, not the ones for the group / team. I have to remember to constantly go back to this. Also, those still don't include the requests from other groups which I have to remember to go through afterwards too.

One page with all merge requests I am participating in that is reachable from everywhere via the main menu top left would be perfect. As this page is already in place, an additional filter to see all requests I am participating in, would fasten our review process and keep our focus on the reviews rather than the right page to go look for them.

How do you use this feature? - On an everyday basis to see a list of all merge requests I still have to do.

Use cases

Any group of developers using GitLab EE for multiple projects with teams (groups) sharing members. Here, each developer will have a great benefit by getting a list of all merge requests they have to do, regardless of which group / project the request belongs to.

Feature checklist

Make sure these are completed before closing the issue, with a link to the relevant commit.