Order epic issues list by position

ee/app/models/ee/epic.rb

@@ -85,9 +85,10 @@ module EE
     end
 
     def issues(current_user)
-      related_issues = ::Issue.select('issues.*, epic_issues.id as epic_issue_id')
+      related_issues = ::Issue.select('issues.*, epic_issues.id as epic_issue_id, epic_issues.position')
         .joins(:epic_issue)
         .where("epic_issues.epic_id = #{id}")
+        .order('epic_issues.position')
 
       Ability.issues_readable_by_user(related_issues, current_user)
     end

ee/app/services/epic_issues/list_service.rb

 module EpicIssues
   class ListService < IssuableLinks::ListService
+    def execute
+      issues.map do |referenced_issue|
+        {
+          id: referenced_issue.id,
+          title: referenced_issue.title,
+          state: referenced_issue.state,
+          reference: reference(referenced_issue),
+          path: project_issue_path(referenced_issue.project, referenced_issue.iid),
+          destroy_relation_path: destroy_relation_path(referenced_issue),
+          epic_issue_id: referenced_issue.epic_issue_id,
+          position: referenced_issue.position
+        }
+      end
+    end
+
     private
 
     def issues