Dont show remove source branch ckecbox/button if you dont have such

permissions for MR page
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/controllers/projects/merge_requests_controller.rb

@@ -225,7 +225,6 @@ class Projects::MergeRequestsController < Projects::ApplicationController
     @merge_request_diff = @merge_request.merge_request_diff
     @allowed_to_merge = allowed_to_merge?
     @show_merge_controls = @merge_request.open? && @commits.any? && @allowed_to_merge
-    @allowed_to_remove_source_branch = allowed_to_remove_source_branch?
     @source_branch = @merge_request.source_project.repository.find_branch(@merge_request.source_branch).try(:name)
   end
 
@@ -238,11 +237,6 @@ class Projects::MergeRequestsController < Projects::ApplicationController
     render 'invalid'
   end
 
-  def allowed_to_remove_source_branch?
-    allowed_to_push_code?(@merge_request.source_project, @merge_request.source_branch) &&
-      !@merge_request.disallow_source_branch_removal?
-  end
-
   def allowed_to_push_code?(project, branch)
     action = if project.protected_branch?(branch)
                :push_code_to_protected_branches

app/models/merge_request.rb

@@ -212,10 +212,6 @@ class MergeRequest < ActiveRecord::Base
     target_project != source_project
   end
 
-  def disallow_source_branch_removal?
-    source_project.root_ref?(source_branch) || source_project.protected_branches.include?(source_branch)
-  end
-
   def project
     target_project
   end

app/views/projects/merge_requests/show/_mr_accept.html.haml

@@ -38,7 +38,7 @@
         .accept-group
           .pull-left
             = f.submit "Accept Merge Request", class: "btn btn-create accept_merge_request"
-          - unless @merge_request.disallow_source_branch_removal?
+          - if can_remove_branch?(@merge_request.source_project, @merge_request.source_branch)
             .remove_branch_holder.pull-left
               = label_tag :should_remove_source_branch, class: "checkbox" do
                 = check_box_tag :should_remove_source_branch

app/views/projects/merge_requests/show/_remove_source_branch.html.haml

 - if @source_branch.blank?
   Source branch has been removed
 
-- elsif @allowed_to_remove_source_branch && @merge_request.merged?
+- elsif can_remove_branch?(@merge_request.source_project, @merge_request.source_branch) && @merge_request.merged?
   .remove_source_branch_widget
     %p Changes merged into #{@merge_request.target_branch}. You can remove source branch now
     = link_to project_branch_path(@merge_request.source_project, @source_branch), remote: true, method: :delete, class: "btn btn-primary btn-small remove_source_branch" do