Merge branch 'entity-api-web-url' into 'master'

api: expose web_url for project entities

## What does this MR do?

Adds a `web_url` field to project snippet, issues, and merge request API returned objects.

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

Tests. Are they sufficient? (I'm working on getting them to pass.)

## Why was this MR needed?

Creating the URL for an MR or issue from the MR is tedious in API libraries; it's easy for Gitlab to just provide it.

## What are the relevant issue numbers?

N/A

## Screenshots (if relevant)

N/A

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] 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 !5631

1 files changed, 12 insertions, 0 deletions

diff --git a/lib/api/entities.rb b/lib/api/entities.rb
index 3ecdc7d448a..5e8729c5342 100644
--- a/lib/api/entities.rb
+++ b/lib/api/entities.rb
@@ -177,6 +177,10 @@ module API
 
       # TODO (rspeicher): Deprecated; remove in 9.0
       expose(:expires_at) { |snippet| nil }
+
+      expose :web_url do |snippet, options|
+        Gitlab::UrlBuilder.build(snippet)
+      end
     end
 
     class ProjectEntity < Grape::Entity
@@ -206,6 +210,10 @@ module API
       expose :user_notes_count
       expose :upvotes, :downvotes
       expose :due_date
+
+      expose :web_url do |issue, options|
+        Gitlab::UrlBuilder.build(issue)
+      end
     end
 
     class ExternalIssue < Grape::Entity
@@ -229,6 +237,10 @@ module API
       expose :user_notes_count
       expose :should_remove_source_branch?, as: :should_remove_source_branch
       expose :force_remove_source_branch?, as: :force_remove_source_branch
+
+      expose :web_url do |merge_request, options|
+        Gitlab::UrlBuilder.build(merge_request)
+      end
     end
 
     class MergeRequestChanges < MergeRequest