function endFnFactory() {
              return function() {
                forEach(animationRunners, function(runner) {
                  // at this point we cannot cancel animations for groups just yet. 1.5+
                  runner.end();
                });
              };
            }
@ngdoc function
@name pascalprecht.translate.$translate#proposedLanguage
@methodOf pascalprecht.translate.$translate

@description
Returns the language key of language that is currently loaded asynchronously.

@return {string} language key