Remove group_milestone_descendants feature flag

Project and subgroup milestones will now be included
on the Roadmap page.

app/graphql/resolvers/milestone_resolver.rb

@@ -52,7 +52,7 @@ module Resolvers
     end
 
     def group_parameters(args)
-      return { group_ids: parent.id } unless include_descendants?(args)
+      return { group_ids: parent.id } unless args[:include_descendants].present?
 
       {
         group_ids: parent.self_and_descendants.public_or_visible_to_user(current_user).select(:id),
@@ -60,10 +60,6 @@ module Resolvers
       }
     end
 
-    def include_descendants?(args)
-      args[:include_descendants].present? && Feature.enabled?(:group_milestone_descendants, parent)
-    end
-
     def group_projects
       GroupProjectsFinder.new(
         group: parent,

changelogs/unreleased/remove-group_milestone_descendants.yml

+---
+title: Include project and subgroup milestones on Roadmap page
+merge_request: 35973
+author:
+type: added

doc/user/group/roadmap/index.md

@@ -12,11 +12,11 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 > - In [GitLab 12.9](https://gitlab.com/gitlab-org/gitlab/-/issues/5164) and later, the epic bars show epics' title, progress, and completed weight percentage.
 > - Milestones appear in roadmaps in [GitLab 12.10](https://gitlab.com/gitlab-org/gitlab/-/issues/6802), and later.
 > - Feature flag for milestones visible in roadmaps removed in [GitLab 13.0](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/29641).
+> - In [GitLab 13.2](https://gitlab.com/gitlab-org/gitlab/-/issues/214375) and later, the Roadmap also shows milestones in projects in a group.
 
-Epics and milestones within a group containing **Start date** and/or **Due date**
-can be visualized in a form of a timeline (that is, a Gantt chart). The Roadmap page
-shows such a visualization for all the epics and milestones which are under a group or one of its
-subgroups.
+Epics and milestones within a group containing a start date or due date can be visualized in a form
+of a timeline (that is, a Gantt chart). The Roadmap page shows the epics and milestones in a
+group, one of its subgroups, or a project in one of the groups.
 
 On the epic bars, you can see the each epic's title, progress, and completed weight percentage.
 When you hover over an epic bar, a popover appears with the epic's title, start date, due date, and

spec/requests/api/graphql/group/milestones_spec.rb

@@ -73,21 +73,6 @@ RSpec.describe 'Milestones through GroupQuery' do
           submilestone_1.to_global_id.to_s, submilestone_2.to_global_id.to_s
         )
       end
-
-      context 'when group_milestone_descendants is disabled' do
-        before do
-          stub_feature_flags(group_milestone_descendants: false)
-        end
-
-        it 'ignores descendant milestones' do
-          fetch_milestones(user, args)
-
-          expect_array_response(
-            milestone_1.to_global_id.to_s, milestone_2.to_global_id.to_s,
-            milestone_3.to_global_id.to_s, milestone_4.to_global_id.to_s
-          )
-        end
-      end
     end
 
     def fetch_milestones(user = nil, args = {})