title: Angularjs $stateProvider and singleton service issue
body: <p>I am using angular-ui-router to make my app organized by routing but I am little confused. as I know I have to add 'ui-router' dependencie in module to use $stateProvider. but even though I do not add 'ui-router' dependencie, It is working well. </p>
  
  <p>I know angular service is singleton object so if I add 'ui-router' dependencie only once. can I use $stateProvider service in any module?</p>
  
  <p>below code is angular code defined in my app.</p>
  
  <pre><code>angular.module('app', ['ui-router','app.pages']);
  
  angular.module('app.pages', ['app.pages.core']);
  
  
  angular.module('app.pages.core',[])
      .config(function ($stateProvider, $urlRouterProvider) {
  
      $stateProvider
          .state('common.default', {
              abstract: true,
              views: {
                  header: {
                      templateUrl: '/public/app/common/components/header/header.html',
                      controller: 'headerController'
  
                  },
                  content: {
                      template: '&lt;div ui-view&gt;&lt;/div&gt;'
                  }
              }
          })
          .state('common.default.core', {
              url: "/goongles/",
              templateUrl: "/public/app/pages/core.html",
              controller: 'coreController'
          });
  });
  </code></pre>
  
  <p>view code</p>
  
  <pre><code>&lt;div ui-view="header"&gt;&lt;/div&gt;
  &lt;div ui-view="content" class ='view ng-scope openm'&gt;&lt;/div&gt;
  </code></pre>
  
  <p>please give me any idea. thanks</p>