When searching we would limit the scope of ancestors to load because
the filter would be applied to the ancestors. Instead, we need to load
_all_ ancestors for matching projects.

For issuable models we keep two timestamps:
updated_at which is updated whenever any model attribute is changed,
last_edited_at which is changed when only title or description is
changed.

In UI bellow description we display who and when updated the item. But
last_edited_by (used for 'who') is mistakenly combined with updated_at
(when), last_edited_at should be used instead.

Closes #41247

The performance bar is still displayed by default in development.

Signed-off-by: Rémy Coutable <remy@rymai.me>

Resolve "Todo notification count shows notification without having a todo"

Closes #40871

See merge request gitlab-org/gitlab-ce!15807

When the target is deleted, todos are destroyed, but we did not reset the todo
cache for users with todos on the deleted target. This would only update after
the next time the todo cache was updated for that user.

* upstream/master: (671 commits)
  Make rubocop happy
  Use guard clause
  Improve language
  Prettify
  Use temp branch
  Pass info about who started the job and which job triggered it
  Docs: add indexes for monitoring and performance monitoring
  clearer-documentation-on-inline-diffs
  Add docs for commit diff discussion in merge requests
  sorting for tags api
  Clear BatchLoader after each spec to prevent holding onto records longer than necessary
  Include project in BatchLoader key to prevent returning blobs for the wrong project
  moved lfs_blob_ids method into ExtractsPath module
  Converted JS modules into exported modules
  spec fixes
  Bump gitlab-shell version to 5.10.3
  Clear caches before updating MR diffs
  Use new Ruby version 2.4 in GitLab QA images
  moved lfs blob fetch from extractspath file
  Update GitLab QA dependencies
  ...