Merge branch '21877-no-mr-branch-title-link-in-issue-on-mobile' into 'master'

Fixed issue merge-request-info missing on mobile

## What does this MR do?

Removed media query declaration relating to `.merge-request-info` and `.issue-info`.

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?

Mobile UX

## Screenshots (if relevant)

![Screen_Shot_2016-09-07_at_19.10.39](/uploads/6dc39b72459087826071ba9fbd06da17/Screen_Shot_2016-09-07_at_19.10.39.png)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #21877

See merge request !6250

app/assets/stylesheets/framework/mobile.scss

@@ -79,10 +79,6 @@
     padding-left: 15px !important;
   }
 
-  .issue-info, .merge-request-info {
-    display: none;
-  }
-
   .nav-links, .nav-links {
     li a {
       font-size: 14px;

app/assets/stylesheets/pages/issues.scss

@@ -37,6 +37,15 @@ form.edit-issue {
   margin: 0;
 }
 
+ul.related-merge-requests > li {
+  display: -ms-flexbox;
+  display: -webkit-flex;
+  display: flex;
+  .merge-request-id {
+    flex-shrink: 0;
+  }
+}
+
 .merge-requests-title, .related-branches-title {
   font-size: 16px;
   font-weight: 600;

app/views/projects/issues/_merge_requests.html.haml

 - if @merge_requests.any?
   %h2.merge-requests-title
     = pluralize(@merge_requests.count, 'Related Merge Request')
-  %ul.unstyled-list
+  %ul.unstyled-list.related-merge-requests
     - has_any_ci = @merge_requests.any?(&:pipeline)
     - @merge_requests.each do |merge_request|
       %li

app/views/projects/issues/_related_branches.html.haml

 - if @related_branches.any?
   %h2.related-branches-title
     = pluralize(@related_branches.count, 'Related Branch')
-  %ul.unstyled-list
+  %ul.unstyled-list.related-merge-requests
     - @related_branches.each do |branch|
       %li
         - target = @project.repository.find_branch(branch).target