title: 3-rd level serialization of embedded objects
body: <p>ember, ember-data 1.0, rails, rabl</p>
  
  <p>I have next json returning from server:</p>
  
  <pre>
  
      {
       "day":{
         "id":5,   
         "expenditures":[{
             "id":10,
             "expense_type":{
               "name":"Very Sad",
               "id":2
             }
           }, 
           {...}
         ]
       }
      }
  
  </pre>
  
  <p>I have next ember models:</p>
  
  <pre>
  
      Expense.Day = DS.Model.extend 
        expenditures: DS.hasMany('expenditure')
  
      Expense.Expenditure = DS.Model.extend 
        day: DS.belongsTo('day')
        expenseType: DS.belongsTo('expenseType')
  
      Expense.ExpenseType = DS.Model.extend 
        name: DS.attr('string')
        expenditures: DS.hasMany('expenditure')
  
  </pre>
  
  <p>And I use ActiveModelSerializer for each model with EmbeddedRecordsMixin, for ex:</p>
  
  <pre>
  
      Expense.DaySerializer = Expense.ApplicationSerializer.extend DS.EmbeddedRecordsMixin,
        attrs:
          expenditures: {embedded: 'always'}
  
      Expense.ExpenditureSerializer = Expense.ApplicationSerializer.extend DS.EmbeddedRecordsMixin,
        attrs:
          expenseType: {embedded: 'always'}
          day: {embedded: 'always'}
  
      Expense.ExpenseTypeSerializer = Expense.ApplicationSerializer.extend DS.EmbeddedRecordsMixin,
        attrs:
          expenditures: {embedded: 'always'}
  
  </pre>
  
  <p>It propertly loads day and expenditures, but not expense_type. I inject into each serializer merhod extract with console.log and super() for debugging and see, that only DaySerializer executed. 
  What's wrong with me? I am very close to insanity with Ember =(</p>