fix a minification issue

app/assets/javascripts/work_packages.js.erb

@@ -39,10 +39,10 @@ var WorkPackage = WorkPackage || {};
     if (!window.angular || button.length < 1) {
       return;
     }
-    angular.element('body').injector().invoke(function($compile) {
+    angular.element('body').injector().invoke(['$compile', function($compile) {
       var scope = angular.element(button).scope();
       $compile(button)(scope);
-    })
+    }])
   };
 
   init = function () {