Merge branch 'new-merge-requests-commit-tab-active' into 'master'

MergeRequest new form load diff asynchronously

## What does this MR do?

Don't return diff tab content from the server when request for a new merge request

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

## Why was this MR needed?

To avoid 502 errors due to this controller action takes to much time

## What are the relevant issue numbers?

Relates #13912

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [x] [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
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5844

1 files changed, 1 insertions, 0 deletions

diff --git a/config/routes/project.rb b/config/routes/project.rb
index 224ec7e8324..0c188478ed1 100644
--- a/config/routes/project.rb
+++ b/config/routes/project.rb
@@ -285,6 +285,7 @@ resources :namespaces, path: '/', constraints: { id: /[a-zA-Z.0-9_\-]+/ }, only:
           get :update_branches
           get :diff_for_path
           post :bulk_update
+          get :new_diffs, path: 'new/diffs'
         end
 
         resources :discussions, only: [], constraints: { id: /\h{40}/ } do