Address requested changes and fix some warnings

MediaBrowser.Controller/SyncPlay/PlaybackRequests/SetShuffleModeGroupRequest.cs

@@ -0,0 +1,27 @@
+using System.Threading;
+using MediaBrowser.Controller.Session;
+using MediaBrowser.Model.SyncPlay;
+
+namespace MediaBrowser.Controller.SyncPlay
+{
+    /// <summary>
+    /// Class SetShuffleModeGroupRequest.
+    /// </summary>
+    public class SetShuffleModeGroupRequest : IGroupPlaybackRequest
+    {
+        /// <summary>
+        /// Gets or sets the shuffle mode.
+        /// </summary>
+        /// <value>The shuffle mode.</value>
+        public string Mode { get; set; }
+
+        /// <inheritdoc />
+        public PlaybackRequestType Type { get; } = PlaybackRequestType.SetShuffleMode;
+
+        /// <inheritdoc />
+        public void Apply(IGroupStateContext context, IGroupState state, SessionInfo session, CancellationToken cancellationToken)
+        {
+            state.HandleRequest(context, state.Type, this, session, cancellationToken);
+        }
+    }
+}