Reinstate branches keyset pagination

Removes branches keyset pagination from behind the feature
flag on the overview part of the GUI. This restores the
overview page to its previous performance improvement.

Changelog: performance

app/controllers/projects/branches_controller.rb

@@ -185,18 +185,12 @@ class Projects::BranchesController < Projects::ApplicationController
     # Here we get one more branch to indicate if there are more data we're not showing
     limit = @overview_max_branches + 1
 
-    if Feature.enabled?(:branch_list_keyset_pagination, project, default_enabled: :yaml)
-      @active_branches =
-        BranchesFinder.new(@repository, { per_page: limit, sort: sort_value_recently_updated })
-          .execute(gitaly_pagination: true).select(&:active?)
-      @stale_branches =
-        BranchesFinder.new(@repository, { per_page: limit, sort: sort_value_oldest_updated })
-          .execute(gitaly_pagination: true).select(&:stale?)
-    else
-      @active_branches, @stale_branches = BranchesFinder.new(@repository, sort: sort_value_recently_updated).execute.partition(&:active?)
-      @active_branches = @active_branches.first(limit)
-      @stale_branches = @stale_branches.first(limit)
-    end
+    @active_branches =
+      BranchesFinder.new(@repository, { per_page: limit, sort: sort_value_recently_updated })
+        .execute(gitaly_pagination: true).select(&:active?)
+    @stale_branches =
+      BranchesFinder.new(@repository, { per_page: limit, sort: sort_value_oldest_updated })
+        .execute(gitaly_pagination: true).select(&:stale?)
 
     @branches = @active_branches + @stale_branches
   end

spec/controllers/projects/branches_controller_spec.rb

@@ -655,21 +655,6 @@ RSpec.describe Projects::BranchesController do
           ["feature", "improve/awesome", "merge-test", "markdown", "feature_conflict", "'test'"]
         )
       end
-
-      context 'branch_list_keyset_pagination is disabled' do
-        before do
-          stub_feature_flags(branch_list_keyset_pagination: false)
-        end
-
-        it 'sets active and stale branches' do
-          expect(assigns[:active_branches].map(&:name)).not_to include(
-            "feature", "improve/awesome", "merge-test", "markdown", "feature_conflict", "'test'"
-          )
-          expect(assigns[:stale_branches].map(&:name)).to eq(
-            ["feature", "improve/awesome", "merge-test", "markdown", "feature_conflict", "'test'"]
-          )
-        end
-      end
     end
   end