#41341

- Change button group width on mobile to 100%
- Added scrolling container to activity top area secondary navigation
- Added bottom border to top-area nav-links to separate them from nav-controls

Uses `list_commits_by_oid` on the CommitService, to request the needed
commits for pipelines. These commits are needed to display the user that
created the commit and the commit title.

This includes fixes for tests failing that depended on the commit
being `nil`. However, now these are batch loaded, this doesn't happen
anymore and the commits are an instance of BatchLoader.

- Only if user can manage project,
- When Auto DevOps is not enabled,
- When project configuration is set to implicit

spacing updates to expander button
sub-title fixes

Given the user can soon have multiple config sources for CI, we now store
what type at the time of the pipeline run we chose. This will give us
insight into what triggered the new pipeline so we can display it to the
enduser.

This got changed for i18n in !12480, however, I forgot to understand
that the meaning of the graphs changed in !12378. This corrects the
behaviour.

[ci skip]

`breadcrumb_title` is then overriden when needed

Earlier, this was part of another MR, but that got split. Didn't pick
that commit, as there were many merge conflicts. Vim macros seemed faster.

This is not ammended to another commit as it will probably have failing
tests which I'll fix and amend to this commit.

Being the good boyscouts, but mainly because of [the comment in the
review](https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/12378#note_33302115)
the words used for classes and variables are changed to not use builds
anymore.

Achieved by using another table, which both has better indexes and
is smaller. Now the data provided for the user is more valueable too.

Close #32994