fix directory watchers not picking up changes

MediaBrowser.Server.Implementations/IO/DirectoryWatchers.cs

@@ -69,7 +69,7 @@ namespace MediaBrowser.Server.Implementations.IO
             // This is an arbitraty amount of time, but delay it because file system writes often trigger events after RemoveTempIgnore has been called. 
             // Seeing long delays in some situations, especially over the network.
             // Seeing delays up to 40 seconds, but not going to ignore changes for that long.
-            await Task.Delay(20000).ConfigureAwait(false);
+            await Task.Delay(1500).ConfigureAwait(false);
 
             string val;
             _tempIgnoredPaths.TryRemove(path, out val);

MediaBrowser.Server.Implementations/Library/LibraryManager.cs

@@ -905,6 +905,20 @@ namespace MediaBrowser.Server.Implementations.Library
         /// <param name="cancellationToken">The cancellation token.</param>
         /// <returns>Task.</returns>
         public async Task ValidateMediaLibraryInternal(IProgress<double> progress, CancellationToken cancellationToken)
+        {
+            _directoryWatchersFactory().Stop();
+
+            try
+            {
+                await PerformLibraryValidation(progress, cancellationToken).ConfigureAwait(false);
+            }
+            finally
+            {
+                _directoryWatchersFactory().Start();
+            }
+        }
+
+        private async Task PerformLibraryValidation(IProgress<double> progress, CancellationToken cancellationToken)
         {
             _logger.Info("Validating media library");
 

MediaBrowser.Server.Implementations/LiveTv/RefreshChannelsScheduledTask.cs

@@ -7,7 +7,7 @@ using System.Threading.Tasks;
 
 namespace MediaBrowser.Server.Implementations.LiveTv
 {
-    class RefreshChannelsScheduledTask : IScheduledTask
+    class RefreshChannelsScheduledTask 
     {
         private readonly ILiveTvManager _liveTvManager;