Add license headers

tests/Avalonia.ReactiveUI.UnitTests/Attributes.cs

@@ -1,3 +1,6 @@
+// Copyright (c) The Avalonia Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
 using Xunit;
 
 // Required to avoid InvalidOperationException sometimes thrown

tests/Avalonia.ReactiveUI.UnitTests/AvaloniaActivationForViewFetcherTest.cs

@@ -1,3 +1,6 @@
+// Copyright (c) The Avalonia Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
 using System;
 using System.Reactive.Concurrency;
 using System.Reactive.Disposables;

tests/Avalonia.ReactiveUI.UnitTests/RoutedViewHostTest.cs

@@ -1,3 +1,6 @@
+// Copyright (c) The Avalonia Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
 using System;
 using System.Reactive.Concurrency;
 using System.Reactive.Disposables;

tests/Avalonia.ReactiveUI.UnitTests/ViewModelViewHostTest.cs

@@ -1,3 +1,6 @@
+// Copyright (c) The Avalonia Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
 using Avalonia.Controls;
 using Avalonia.UnitTests;
 using ReactiveUI;