Removes custom backend @Redmine::I18n::Backend@ (#42859):

* move custom logic to get the available locales by looking at translation file names to @config.i18n.available_locales@ option.
* remove unnecessary fallback include which does the same thing as @config.i18n.fallbacks = true@.
* include custom pluralization rules as Rails suggests.

git-svn-id: https://svn.redmine.org/redmine/trunk@23830 e93f8b46-1217-0410-a6f0-8f06a7374b81

config/application.rb

@@ -59,6 +59,7 @@ module RedmineApp
     config.i18n.enforce_available_locales = true
     config.i18n.fallbacks = true
     config.i18n.default_locale = 'en'
+    config.i18n.available_locales = Dir[Rails.root / 'config' / 'locales' / '*.yml'].map { |f| File.basename(f, '.yml').to_sym }
 
     # Configure the default encoding used in templates for Ruby 1.9.
     config.encoding = "utf-8"

config/initializers/30-redmine.rb

@@ -4,9 +4,7 @@ require 'redmine/configuration'
 require 'redmine/plugin_loader'
 
 Rails.application.config.to_prepare do
-  I18n.backend = Redmine::I18n::Backend.new
-  # Forces I18n to load available locales from the backend
-  I18n.config.available_locales = nil
+  I18n::Backend::Simple.include(I18n::Backend::Pluralization)
 
   # Use Nokogiri as XML backend instead of Rexml
   ActiveSupport::XmlMini.backend = 'Nokogiri'

lib/redmine/i18n.rb

@@ -173,22 +173,5 @@ module Redmine
     def current_language
       ::I18n.locale
     end
-
-    # Custom backend based on I18n::Backend::Simple with the following changes:
-    # * available_locales are determined by looking at translation file names
-    class Backend < ::I18n::Backend::Simple
-      # Get available locales from the translations filenames
-      def available_locales
-        @available_locales ||= begin
-          redmine_locales = Dir[Rails.root / 'config' / 'locales' / '*.yml'].map { |f| File.basename(f, '.yml').to_sym }
-          super & redmine_locales
-        end
-      end
-
-      # Adds custom pluralization rules
-      include ::I18n::Backend::Pluralization
-      # Adds fallback to default locale for untranslated strings
-      include ::I18n::Backend::Fallbacks
-    end
   end
 end