Merge branch 'url-builder-fix-for-relative-urls' into 'master'

Fix URL construction for merge requests, issues, notes, and commits for relative URL config

This MR fixes the constructor of URL links for systems using relative URLs in the application config. The `host` parameter was used improperly, supplying an extra path (e.g. https://mydomain.com/gitlab) and unnecessary scheme. We should be able to default to the URL options set in `8_default_url_options.rb` file.

Closes https://github.com/gitlabhq/gitlabhq/issues/9605

See merge request !1250

CHANGELOG

 Please view this file on the master branch, on stable branches it's out of date.
 
 v 8.0.0 (unreleased)
+  - Fix URL construction for merge requests, issues, notes, and commits for relative URL config (Stan Hu)
   - Omit filename in Content-Disposition header in raw file download to avoid RFC 6266 encoding issues (Stan HU)
   - Fix broken Wiki Page History (Stan Hu)
   - Prevent anchors from being hidden by header (Stan Hu)

lib/gitlab/url_builder.rb

@@ -23,12 +23,12 @@ module Gitlab
 
     def build_issue_url(id)
       issue = Issue.find(id)
-      issue_url(issue, host: Gitlab.config.gitlab['url'])
+      issue_url(issue)
     end
 
     def build_merge_request_url(id)
       merge_request = MergeRequest.find(id)
-      merge_request_url(merge_request, host: Gitlab.config.gitlab['url'])
+      merge_request_url(merge_request)
     end
 
     def build_note_url(id)
@@ -37,22 +37,18 @@ module Gitlab
         namespace_project_commit_url(namespace_id: note.project.namespace,
                                      id: note.commit_id,
                                      project_id: note.project,
-                                     host: Gitlab.config.gitlab['url'],
                                      anchor: "note_#{note.id}")
       elsif note.for_issue?
         issue = Issue.find(note.noteable_id)
         issue_url(issue,
-                  host: Gitlab.config.gitlab['url'],
                   anchor: "note_#{note.id}")
       elsif note.for_merge_request?
         merge_request = MergeRequest.find(note.noteable_id)
         merge_request_url(merge_request,
-                          host: Gitlab.config.gitlab['url'],
                           anchor: "note_#{note.id}")
       elsif note.for_project_snippet?
         snippet = Snippet.find(note.noteable_id)
         project_snippet_url(snippet,
-                            host: Gitlab.config.gitlab['url'],
                             anchor: "note_#{note.id}")
       end
     end