Remove unused method Mailer#mylogger (#28028).

Patch by Go MAEDA.


git-svn-id: http://svn.redmine.org/redmine/trunk@17197 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/mailer.rb

@@ -581,8 +581,4 @@ class Mailer < ActionMailer::Base
     @references_objects ||= []
     @references_objects << object
   end
-
-  def mylogger
-    Rails.logger
-  end
 end