Merge branch 'issues-tracker-id' into 'master'

Properly move over `issues_tracker_id` from old custom issue tracker URLs.

Addresses https://gitlab.com/gitlab-org/gitlab-ce/issues/1124.

cc @marin Regression in 7.8.0.

See merge request !1670

app/models/project_services/issue_tracker_service.rb

@@ -55,9 +55,9 @@ class IssueTrackerService < Service
       if enabled_in_gitlab_config
         self.properties = {
           title: issues_tracker['title'],
-          project_url: set_project_url,
-          issues_url: issues_tracker['issues_url'],
-          new_issue_url: issues_tracker['new_issue_url']
+          project_url: add_issues_tracker_id(issues_tracker['project_url']),
+          issues_url: add_issues_tracker_id(issues_tracker['issues_url']),
+          new_issue_url: add_issues_tracker_id(issues_tracker['new_issue_url'])
         }
       else
         self.properties = {}
@@ -100,15 +100,15 @@ class IssueTrackerService < Service
     Gitlab.config.issues_tracker[to_param]
   end
 
-  def set_project_url
+  def add_issues_tracker_id(url)
     if self.project
       id = self.project.issues_tracker_id
 
       if id
-        issues_tracker['project_url'].gsub(":issues_tracker_id", id)
+        url = url.gsub(":issues_tracker_id", id)
       end
     end
 
-    issues_tracker['project_url']
+    url
   end
 end