https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4964#note_12744656

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4964#note_12741046

We store the sizes as a hash from path to bytes like:

``` ruby
{'ci_artifacts.txt' => 27,
 'other_artifacts_0.1.2/another-subdirectory/banana_sample.gif' =>
71759,
 'other_artifacts_0.1.2/doc_sample.txt' => 1314,
 'rails_sample.jpg' => 35255,
 'tests_encoding/utf8 test dir ✓/regular_file_2' => 7}
```

So that it's easier to access than reading gzip file again.

* upstream/master: (337 commits)
  Update CHANGELOG for !4659
  Center the header logo for all Devise emails
  Add previews for all customized Devise emails
  Customize the Devise `unlock_instructions` email
  Customize the Devise `reset_password_instructions` email
  Customize the Devise `password_change` emails
  Use gitlab-git 10.2.0
  Use Git cached counters on project show page
  Fix indentation scss-lint errors
  Added title attribute to enties in tree view Closes #18353
  Banzai::Filter::ExternalLinkFilter use XPath
  Reduce queries in IssueReferenceFilter
  Use gitlab_git 10.1.4
  Fixed ordering in Project.find_with_namespace
  Fix images in emails
  Banzai::Filter::UploadLinkFilter use XPath
  Turn Group#owners into a has_many association
  Make project_id nullable
  CHANGELOG [ci skip]
  CHANGELOG [ci skip]
  ...

* master: (147 commits)
  Update CHANGELOG
  Remove deprecated issues_tracker and issues_tracker_id from project
  Schema doesn’t reflect the changes of the last 3 migrations
  Revert CHANGELOG
  Also rename "find" in the specs
  Change to new Notes styleguide
  Add guide on changing a document's location
  Change logs.md location in README
  Move logs/logs.md to administration/logs.md
  Make "four phase test"
  Only show branches for revert / cherry-pick
  Instrument all Banzai::ReferenceParser classes
  Removed old comment from update_column_in_batches
  Update columns in batches until no rows are left
  Remove counters from Pipeline navigation
  Handle NULL migration errors in migration helpers
  Fix typo causing related branches to Error 500
  Improved SVG sanitizer specs to include smoke tests for clean.
  Refactored SVG sanitizer
  Added SVG sanitizer fix to the changelog
  ...