Generate contact code manually

Generate contact's code explicitly on contact:create epp request and domain transfer. Remove callback.

app/controllers/epp/contacts_controller.rb

@@ -21,14 +21,15 @@ class Epp::ContactsController < EppController
     @contact = Epp::Contact.new(frame, current_user.registrar)
 
     @contact.add_legal_file_to_new(frame)
-
-    @response_code = if Contact.address_processing?
-                           1000
-                         else
-                           frame.css('postalInfo addr').size != 0 ? 1100 : 1000
-                         end
+    @contact.generate_code
 
     if @contact.save
+      @response_code = if Contact.address_processing?
+                         1000
+                       else
+                         frame.css('postalInfo addr').size != 0 ? 1100 : 1000
+                       end
+
       render_epp_response '/epp/contacts/create'
     else
       handle_errors(@contact)

app/models/contact.rb

@@ -45,7 +45,6 @@ class Contact < ActiveRecord::Base
   end
 
   before_validation :to_upcase_country_code
-  before_validation :prefix_code
   before_validation :strip_email
   before_create :generate_auth_info
 
@@ -366,7 +365,7 @@ class Contact < ActiveRecord::Base
   end
 
   # rubocop:disable Metrics/CyclomaticComplexity
-  def prefix_code
+  def generate_code
     return nil unless new_record?
     return nil if registrar.blank?
     code = self[:code]

app/models/epp/domain.rb

@@ -646,7 +646,7 @@ class Epp::Domain < Domain
     oc.code = nil
     oc.registrar_id = registrar_id
     oc.copy_from_id = c.id
-    oc.prefix_code
+    oc.generate_code
     oc.domain_transfer = true
     oc.save!(validate: false)
     oc