Adapt karma js tests for i18n-js

lib/tasks/karma.rake

@@ -39,11 +39,9 @@ namespace :karma  do
   end
 
   def i18n_file
-    I18n.backend.send(:init_translations) unless I18n.backend.initialized?
-    f = Tempfile.open('i18n.js', Rails.root.join('tmp') )
-    f.write 'window.I18n = '
-    f.write I18n.backend.send(:translations)[I18n.locale].with_indifferent_access.to_json.html_safe
-    f.flush
-    f.path
+    raise "I18n::JS module is missing" unless defined?(I18n::JS)
+    I18n::JS::DEFAULT_EXPORT_DIR_PATH.replace('tmp/javascripts')
+    I18n::JS.export
+    "#{Rails.root.join(I18n::JS::DEFAULT_EXPORT_DIR_PATH)}/translations.js"
   end
 end

spec/javascripts/application_spec.js

@@ -13,6 +13,7 @@
 //= require textAngular-sanitize.min.js
 //= require textAngular.min.js
 //= require moment
+//= require i18n
 
 angular.module('templates', [])
 angular.module('google-maps', []);