Address reviewer feedback

- Remove unneeded FOSS placeholder
- Place model in boards namespace

db/migrate/20201119003042_add_epic_board_positions.rb

@@ -5,23 +5,23 @@ class AddEpicBoardPositions < ActiveRecord::Migration[6.0]
 
   DOWNTIME = false
 
-  disable_ddl_transaction!
-
   def up
     with_lock_retries do
-      create_table :epic_board_positions do |t|
+      create_table :boards_epic_board_positions do |t|
         t.references :board, foreign_key: { on_delete: :cascade }, null: false, index: false
         t.references :epic, foreign_key: { on_delete: :cascade }, null: false, index: true
         t.integer :relative_position
 
         t.timestamps_with_timezone null: false
 
-        t.index [:board_id, :epic_id], unique: true, name: :index_epic_board_positions_on_board_id_and_epic_id
+        t.index [:board_id, :epic_id], unique: true, name: :index_boards_epic_board_positions_on_board_id_and_epic_id
       end
     end
   end
 
   def down
-    drop_table :epic_board_positions
+    with_lock_retries do
+      drop_table :boards_epic_board_positions
+    end
   end
 end

ee/app/models/boards/epic_board_position.rb

+# frozen_string_literal: true
+
+module Boards
+  class EpicBoardPosition < ApplicationRecord
+    include RelativePositioning
+
+    self.table_name = 'boards_epic_board_positions'
+
+    belongs_to :board
+    belongs_to :epic
+
+    validates :board, presence: true
+    validates :epic, presence: true, uniqueness: { scope: :board_id }
+
+    alias_attribute :parent, :board
+
+    scope :order_relative_position, -> do
+      reorder('relative_position ASC', 'id DESC')
+    end
+
+    def self.relative_positioning_query_base(position)
+      where(board_id: position.board_id)
+    end
+
+    def self.relative_positioning_parent_column
+      :board_id
+    end
+  end
+end

ee/app/models/ee/epic_board_position.rb

-# frozen_string_literal: true
-
-module EE
-  module EpicBoardPosition
-    extend ActiveSupport::Concern
-
-    prepended do
-      include RelativePositioning
-
-      belongs_to :board
-      belongs_to :epic
-
-      validates :board, presence: true
-      validates :epic, presence: true, uniqueness: { scope: :board_id }
-
-      alias_attribute :parent, :board
-
-      scope :order_relative_position, -> do
-        reorder('relative_position ASC', 'id DESC')
-      end
-    end
-
-    class_methods do
-      extend ::Gitlab::Utils::Override
-
-      def relative_positioning_query_base(position)
-        where(board_id: position.board_id)
-      end
-
-      def relative_positioning_parent_column
-        :board_id
-      end
-    end
-  end
-end

ee/spec/factories/epic_board_positions.rb

 # frozen_string_literal: true
 
 FactoryBot.define do
-  factory :epic_board_position do
+  factory :epic_board_position, class: 'Boards::EpicBoardPosition' do
     epic
     board
     relative_position { RelativePositioning::START_POSITION }

ee/spec/models/epic_board_position_spec.rb → ee/spec/models/boards/epic_board_position_spec.rb

@@ -2,7 +2,7 @@
 
 require 'spec_helper'
 
-RSpec.describe EpicBoardPosition do
+RSpec.describe Boards::EpicBoardPosition do
   let_it_be(:epic) { create(:epic) }
   let_it_be(:group) { create(:group) }
   let_it_be(:board) { create(:board, group: group) }