fix mocks.

tests/Avalonia.Controls.UnitTests/DesktopStyleApplicationLifetimeTests.cs

@@ -192,6 +192,7 @@ namespace Avalonia.Controls.UnitTests
             var windowImpl = new Mock<IWindowImpl>();
             windowImpl.SetupProperty(x => x.Closed);
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
+            windowImpl.Setup(x => x.RenderScaling).Returns(1);
 
             var services = TestServices.StyledWindow.With(
                 windowingPlatform: new MockWindowingPlatform(() => windowImpl.Object));

tests/Avalonia.UnitTests/MockWindowingPlatform.cs

@@ -30,6 +30,7 @@ namespace Avalonia.UnitTests
             windowImpl.Setup(x => x.ClientSize).Returns(() => clientSize);
             windowImpl.Setup(x => x.MaxAutoSizeHint).Returns(s_screenSize);
             windowImpl.Setup(x => x.DesktopScaling).Returns(1);
+            windowImpl.Setup(x => x.RenderScaling).Returns(1);
             windowImpl.Setup(x => x.Screen).Returns(CreateScreenMock().Object);
             windowImpl.Setup(x => x.Position).Returns(() => position);
             SetupToplevel(windowImpl);