NoMethodError: protected method `labels' called for #<Gitlab::Metrics::BackgroundTransaction:0x00007fd874312b90>

With EE master, I see:

15:54:29 rails-background-jobs.1 | 2017-11-07T23:54:29.831Z 59805 TID-owvz07xxk WARN: NoMethodError: protected method `labels' called for #<Gitlab::Metrics::BackgroundTransaction:0x00007fd874312b90>
15:54:29 rails-background-jobs.1 | 2017-11-07T23:54:29.832Z 59805 TID-owvz07xxk WARN: /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/metrics/subscribers/rails_cache.rb:51:in `observe'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/metrics/subscribers/rails_cache.rb:10:in `cache_read'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/subscriber.rb:100:in `finish'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/notifications/fanout.rb:102:in `finish'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/notifications/fanout.rb:46:in `block in finish'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/notifications/fanout.rb:46:in `each'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/notifications/fanout.rb:46:in `finish'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/notifications/instrumenter.rb:36:in `finish'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/notifications/instrumenter.rb:25:in `instrument'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/notifications.rb:164:in `instrument'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/cache.rb:547:in `instrument'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/cache.rb:556:in `find_cached_entry'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/activesupport-4.2.8/lib/active_support/cache.rb:293:in `fetch'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/geo.rb:140:in `block in cache_value'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/request_store-1.3.1/lib/request_store.rb:47:in `fetch'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/geo.rb:140:in `cache_value'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/geo.rb:41:in `enabled?'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/app/services/geo/metrics_update_service.rb:6:in `execute'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/metrics/instrumentation.rb:159:in `block in execute'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/metrics/method_call.rb:53:in `measure'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/lib/gitlab/metrics/instrumentation.rb:159:in `execute'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/app/workers/geo/metrics_update_worker.rb:12:in `block in perform'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/app/services/concerns/exclusive_lease_guard.rb:22:in `try_obtain_lease'
15:54:29 rails-background-jobs.1 | /Users/stanhu/gitlab/gdk-ee/gitlab/app/workers/geo/metrics_update_worker.rb:12:in `perform'
15:54:29 rails-background-jobs.1 | /Users/stanhu/.rbenv/versions/2.3.5/lib/ruby/gems/2.3.0/gems/sidekiq-5.0.4/lib/sidekiq/processor.rb:199:in `execute_job'