optimize code

app/models/user.rb

@@ -57,6 +57,8 @@
 
   before_validation :clean_document_number
 
+  before_create :set_password_changed_at
+
   # Get the existing user by email if the provider gives us a verified email.
   def self.first_or_initialize_for_oauth(auth)
     oauth_email           = auth.info.email
@@ -240,6 +242,10 @@
     true
   end
 
+  def set_password_changed_at
+    set_password_changed_at = created_at
+  end 
+
   def ability
     @ability ||= Ability.new(self)
   end