Unify empty array initializations

LibVLCSharp/Shared/LibVLC.cs

@@ -662,7 +662,12 @@ namespace LibVLCSharp.Shared
                 var discoverList = IntPtr.Zero;
                 var count = Native.LibVLCRendererDiscovererGetList(NativeReference, ref discoverList);
 
-                if (count == 0) return new RendererDescription[0];
+                if (count == 0)
+#if NETSTANDARD1_1 || NET40
+                    return new RendererDescription[0];
+#else
+                    return Array.Empty<RendererDescription>();
+#endif
 
                 var rendererDiscovererDescription = new RendererDescription[(int)count];
 

LibVLCSharp/Shared/MediaPlayer.cs

@@ -1158,8 +1158,12 @@ namespace LibVLCSharp.Shared
 
         TrackDescription[] GetTrackDescription(IntPtr trackPtr)
         {
-            if (trackPtr == IntPtr.Zero) return new TrackDescription[0];
-
+            if (trackPtr == IntPtr.Zero)
+#if NETSTANDARD1_1 || NET40
+                return new TrackDescription[0];
+#else
+                return Array.Empty<TrackDescription>();
+#endif
             var trackDescriptions = new List<TrackDescription>();
             var track = MarshalUtils.PtrToStructure<TrackDescription>(trackPtr);