Remove IsEmpty and Empty members

These were only removed for relevant/discussed types. Collections and some other lesser used types still have IsEmpty properties.

src/Avalonia.Base/CornerRadius.cs

@@ -65,10 +65,6 @@ namespace Avalonia
         /// </summary>
         public bool IsDefault => TopLeft == 0 && TopRight == 0 && BottomLeft == 0 && BottomRight == 0;
 
-        /// <inheritdoc cref="IsDefault"/>
-        [Obsolete("Use IsDefault instead.")]
-        public bool IsEmpty => IsDefault;
-
         /// <summary>
         /// Gets a value indicating whether all corner radii are equal.
         /// </summary>

src/Avalonia.Base/Media/BoxShadow.cs

@@ -50,10 +50,6 @@ namespace Avalonia.Media
         /// </summary>
         public bool IsDefault => OffsetX == 0 && OffsetY == 0 && Blur == 0 && Spread == 0;
 
-        /// <inheritdoc cref="IsDefault"/>
-        [Obsolete("Use IsDefault instead.")]
-        public bool IsEmpty => IsDefault;
-
         private readonly static char[] s_Separator = new char[] { ' ', '\t' };
 
         struct ArrayReader

src/Avalonia.Base/PixelRect.cs

@@ -9,12 +9,6 @@ namespace Avalonia
     /// </summary>
     public readonly struct PixelRect : IEquatable<PixelRect>
     {
-        /// <summary>
-        /// An empty rectangle.
-        /// </summary>
-        [Obsolete("Use the default keyword instead.")]
-        public static readonly PixelRect Empty = default;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="PixelRect"/> structure.
         /// </summary>
@@ -138,10 +132,6 @@ namespace Avalonia
         /// </summary>
         public bool IsDefault => Width == 0 && Height == 0;
 
-        /// <inheritdoc cref="IsDefault"/>
-        [Obsolete("Use IsDefault instead.")]
-        public bool IsEmpty => IsDefault;
-
         /// <summary>
         /// Checks for equality between two <see cref="PixelRect"/>s.
         /// </summary>

src/Avalonia.Base/Rect.cs

@@ -16,12 +16,6 @@ namespace Avalonia
             Animation.Animation.RegisterAnimator<RectAnimator>(prop => typeof(Rect).IsAssignableFrom(prop.PropertyType));
         }
 
-        /// <summary>
-        /// An empty rectangle.
-        /// </summary>
-        [Obsolete("Use the default keyword instead.")]
-        public static readonly Rect Empty = default;
-
         /// <summary>
         /// The X position.
         /// </summary>
@@ -177,10 +171,6 @@ namespace Avalonia
         public bool IsDefault => _width == 0 && _height == 0;
         // ReSharper restore CompareOfFloatsByEqualityOperator
 
-        /// <inheritdoc cref="IsDefault"/>
-        [Obsolete("Use IsDefault instead.")]
-        public bool IsEmpty => IsDefault;
-
         /// <summary>
         /// Checks for equality between two <see cref="Rect"/>s.
         /// </summary>

src/Avalonia.Base/Size.cs

@@ -27,12 +27,6 @@ namespace Avalonia
         /// </summary>
         public static readonly Size Infinity = new Size(double.PositiveInfinity, double.PositiveInfinity);
 
-        /// <summary>
-        /// A size representing zero.
-        /// </summary>
-        [Obsolete("Use the default keyword instead.")]
-        public static readonly Size Empty = new Size(0, 0);
-
         /// <summary>
         /// The width.
         /// </summary>

src/Avalonia.Base/Thickness.cs

@@ -97,10 +97,6 @@ namespace Avalonia
         /// </summary>
         public double Bottom => _bottom;
 
-        /// <inheritdoc cref="IsDefault"/>
-        [Obsolete("Use IsDefault instead.")]
-        public bool IsEmpty => IsDefault;
-
         /// <summary>
         /// Gets a value indicating whether all sides are equal.
         /// </summary>