only set creation date at resolve time

MediaBrowser.Controller/Entities/BaseItem.cs

@@ -354,7 +354,7 @@ namespace MediaBrowser.Controller.Entities
             }
 
             //update our dates
-            EntityResolutionHelper.EnsureDates(this, args);
+            EntityResolutionHelper.EnsureDates(this, args, false);
 
             IsOffline = false;
 

MediaBrowser.Controller/Entities/Folder.cs

@@ -681,7 +681,7 @@ namespace MediaBrowser.Controller.Entities
                     //existing item - check if it has changed
                     if (currentChild.HasChanged(child))
                     {
-                        EntityResolutionHelper.EnsureDates(currentChild, child.ResolveArgs);
+                        EntityResolutionHelper.EnsureDates(currentChild, child.ResolveArgs, false);
 
                         validChildren.Add(new Tuple<BaseItem, bool>(currentChild, true));
                     }

MediaBrowser.Controller/Resolvers/EntityResolutionHelper.cs

@@ -127,7 +127,8 @@ namespace MediaBrowser.Controller.Resolvers
         /// </summary>
         /// <param name="item">The item.</param>
         /// <param name="args">The args.</param>
-        public static void EnsureDates(BaseItem item, ItemResolveArgs args)
+        /// <param name="includeCreationTime">if set to <c>true</c> [include creation time].</param>
+        public static void EnsureDates(BaseItem item, ItemResolveArgs args, bool includeCreationTime)
         {
             if (!Path.IsPathRooted(item.Path))
             {
@@ -140,8 +141,12 @@ namespace MediaBrowser.Controller.Resolvers
                 var childData = args.IsDirectory ? args.GetFileSystemEntryByPath(item.Path) : null;
 
                 if (childData != null)
+                {
+                    if (includeCreationTime)
                     {
                         item.DateCreated = childData.CreationTimeUtc;
+                    }
+
                     item.DateModified = childData.LastWriteTimeUtc;
                 }
                 else
@@ -149,15 +154,21 @@ namespace MediaBrowser.Controller.Resolvers
                     var fileData = FileSystem.GetFileSystemInfo(item.Path);
 
                     if (fileData.Exists)
+                    {
+                        if (includeCreationTime)
                         {
                             item.DateCreated = fileData.CreationTimeUtc;
+                        }
                         item.DateModified = fileData.LastWriteTimeUtc;
                     }
                 }
             }
             else
+            {
+                if (includeCreationTime)
                 {
                     item.DateCreated = args.FileInfo.CreationTimeUtc;
+                }
                 item.DateModified = args.FileInfo.LastWriteTimeUtc;
             }
         }

MediaBrowser.Server.Implementations/Library/ResolverHelper.cs

@@ -48,7 +48,7 @@ namespace MediaBrowser.Server.Implementations.Library
             item.DontFetchMeta = item.Path.IndexOf("[dontfetchmeta]", StringComparison.OrdinalIgnoreCase) != -1;
 
             // Make sure DateCreated and DateModified have values
-            EntityResolutionHelper.EnsureDates(item, args);
+            EntityResolutionHelper.EnsureDates(item, args, true);
         }
 
         /// <summary>