MR Widget Refactor Part 2
Second MR of the MR widget refactor work.
Previous MR is already merged into mr-widget-redesign-review
branch. This MR's target branch is also mr-widget-redesign-review
. We are doing this because of incremental reviews.
This can be merged into review branch whenever reviewer thinks it's OK. I stop pipelines intentionally.
Related with https://gitlab.com/gitlab-org/gitlab-ce/issues/25424