backout r11875 ApplicationHelperTest change

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@11876 e93f8b46-1217-0410-a6f0-8f06a7374b81
include Redmine::I18n in ApplicationHelperTest

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@11877 e93f8b46-1217-0410-a6f0-8f06a7374b81