Minor improvements

MediaBrowser.Controller/Chapters/IChapterManager.cs

@@ -1,16 +1,17 @@
+using System;
 using System.Collections.Generic;
 using MediaBrowser.Model.Entities;
 
 namespace MediaBrowser.Controller.Chapters
 {
     /// <summary>
-    /// Interface IChapterManager
+    /// Interface IChapterManager.
     /// </summary>
     public interface IChapterManager
     {
         /// <summary>
         /// Saves the chapters.
         /// </summary>
-        void SaveChapters(string itemId, List<ChapterInfo> chapters);
+        void SaveChapters(Guid itemId, IReadOnlyList<ChapterInfo> chapters);
     }
 }