Backport changes from gitlab-org/gitlab-ee!581 to CE.

!581 has a lot of changes that would cause merge conflicts if not
properly backported to CE. This commit/MR serves as a better
foundation for gitlab-org/gitlab-ee!581.

= Changes =

1. Move from `has_one {merge,push}_access_level` to `has_many`, with the
   `length` of the association limited to `1`. This is _effectively_ a
   `has_one` association, but should cause less conflicts with EE, which
   is set to `has_many`. This has a number of related changes in the
   views, specs, and factories.

2. Make `gon` variable loading more consistent (with EE!581) in the
   `ProtectedBranchesController`. Also use `::` to prefix the
   `ProtectedBranches` services, because this is required in EE.

3. Extract a `ProtectedBranchAccess` concern from the two access level
   models. This concern only has a single `humanize` method here, but
   will have more methods in EE.

4. Add `form_errors` to the protected branches creation form. This is
   not strictly required for EE compatibility, but was an oversight
   nonetheless.

1 files changed, 5 insertions, 5 deletions

diff --git a/spec/factories/protected_branches.rb b/spec/factories/protected_branches.rb
index 5575852c2d7..3b21174987f 100644
--- a/spec/factories/protected_branches.rb
+++ b/spec/factories/protected_branches.rb
@@ -4,25 +4,25 @@ FactoryGirl.define do
     project
 
     after(:create) do |protected_branch|
-      protected_branch.create_push_access_level!(access_level: Gitlab::Access::MASTER)
-      protected_branch.create_merge_access_level!(access_level: Gitlab::Access::MASTER)
+      protected_branch.push_access_levels.create!(access_level: Gitlab::Access::MASTER)
+      protected_branch.merge_access_levels.create!(access_level: Gitlab::Access::MASTER)
     end
 
     trait :developers_can_push do
       after(:create) do |protected_branch|
-        protected_branch.push_access_level.update!(access_level: Gitlab::Access::DEVELOPER)
+        protected_branch.push_access_levels.first.update!(access_level: Gitlab::Access::DEVELOPER)
       end
     end
 
     trait :developers_can_merge do
       after(:create) do |protected_branch|
-        protected_branch.merge_access_level.update!(access_level: Gitlab::Access::DEVELOPER)
+        protected_branch.merge_access_levels.first.update!(access_level: Gitlab::Access::DEVELOPER)
       end
     end
 
     trait :no_one_can_push do
       after(:create) do |protected_branch|
-        protected_branch.push_access_level.update!(access_level: Gitlab::Access::NO_ACCESS)
+        protected_branch.push_access_levels.first.update!(access_level: Gitlab::Access::NO_ACCESS)
       end
     end
   end