Init jira issue breadcrumb

app/helpers/services_helper.rb

@@ -128,6 +128,13 @@ module ServicesHelper
     !Gitlab.com?
   end
 
+  def jira_issue_breadcrumb_link(issue_json)
+    link_to '', { class: 'gl-display-flex gl-align-items-center gl-white-space-nowrap' } do
+      icon = image_tag image_path('illustrations/logos/jira.svg'), width: 15, height: 15, class: 'gl-mr-2'
+      [icon, issue_json[:references][:relative]].join.html_safe
+    end
+  end
+
   extend self
 
   private

ee/app/controllers/projects/integrations/jira/issues_controller.rb

@@ -37,6 +37,8 @@ module Projects
         end
 
         def show
+          @issue = issue_json
+
           respond_to do |format|
             format.html
             format.json do

ee/app/views/projects/integrations/jira/issues/show.html.haml

 - add_to_breadcrumbs _('Jira Issues'), project_integrations_jira_issues_path(@project)
-- page_title 'Jira issue'
+- breadcrumb_title jira_issue_breadcrumb_link(@issue)
+- page_title @issue[:title]
 
 .js-jira-issues-show-app{ data: jira_issues_show_data }