Make concrete binding plugin classes internal.

src/Avalonia.Base/Data/Core/Plugins/AvaloniaPropertyAccessorPlugin.cs

@@ -8,7 +8,7 @@ namespace Avalonia.Data.Core.Plugins
     /// <summary>
     /// Reads a property from a <see cref="AvaloniaObject"/>.
     /// </summary>
-    public class AvaloniaPropertyAccessorPlugin : IPropertyAccessorPlugin
+    internal class AvaloniaPropertyAccessorPlugin : IPropertyAccessorPlugin
     {
         /// <inheritdoc/>
         [RequiresUnreferencedCode(TrimmingMessages.PropertyAccessorsRequiresUnreferencedCodeMessage)]

src/Avalonia.Base/Data/Core/Plugins/DataAnnotationsValidationPlugin.cs

@@ -10,7 +10,7 @@ namespace Avalonia.Data.Core.Plugins
     /// <summary>
     /// Validates properties on that have <see cref="ValidationAttribute"/>s.
     /// </summary>
-    public class DataAnnotationsValidationPlugin : IDataValidationPlugin
+    internal class DataAnnotationsValidationPlugin : IDataValidationPlugin
     {
         /// <inheritdoc/>
         [RequiresUnreferencedCode(TrimmingMessages.DataValidationPluginRequiresUnreferencedCodeMessage)]

src/Avalonia.Base/Data/Core/Plugins/ExceptionValidationPlugin.cs

@@ -7,7 +7,7 @@ namespace Avalonia.Data.Core.Plugins
     /// <summary>
     /// Validates properties that report errors by throwing exceptions.
     /// </summary>
-    public class ExceptionValidationPlugin : IDataValidationPlugin
+    internal class ExceptionValidationPlugin : IDataValidationPlugin
     {
         /// <inheritdoc/>
         [RequiresUnreferencedCode(TrimmingMessages.DataValidationPluginRequiresUnreferencedCodeMessage)]

src/Avalonia.Base/Data/Core/Plugins/IndeiValidationPlugin.cs

@@ -10,7 +10,7 @@ namespace Avalonia.Data.Core.Plugins
     /// <summary>
     /// Validates properties on objects that implement <see cref="INotifyDataErrorInfo"/>.
     /// </summary>
-    public class IndeiValidationPlugin : IDataValidationPlugin
+    internal class IndeiValidationPlugin : IDataValidationPlugin
     {
         private static readonly WeakEvent<INotifyDataErrorInfo, DataErrorsChangedEventArgs>
             ErrorsChangedWeakEvent = WeakEvent.Register<INotifyDataErrorInfo, DataErrorsChangedEventArgs>(

src/Avalonia.Base/Data/Core/Plugins/InpcPropertyAccessorPlugin.cs

@@ -11,7 +11,7 @@ namespace Avalonia.Data.Core.Plugins
     /// Reads a property from a standard C# object that optionally supports the
     /// <see cref="INotifyPropertyChanged"/> interface.
     /// </summary>
-    public class InpcPropertyAccessorPlugin : IPropertyAccessorPlugin
+    internal class InpcPropertyAccessorPlugin : IPropertyAccessorPlugin
     {
         private readonly Dictionary<(Type, string), PropertyInfo?> _propertyLookup =
             new Dictionary<(Type, string), PropertyInfo?>();

src/Avalonia.Base/Data/Core/Plugins/MethodAccessorPlugin.cs

@@ -6,7 +6,7 @@ using System.Reflection;
 
 namespace Avalonia.Data.Core.Plugins
 {
-    public class MethodAccessorPlugin : IPropertyAccessorPlugin
+    internal class MethodAccessorPlugin : IPropertyAccessorPlugin
     {
         private readonly Dictionary<(Type, string), MethodInfo?> _methodLookup =
             new Dictionary<(Type, string), MethodInfo?>();

src/Avalonia.Base/Data/Core/Plugins/ObservableStreamPlugin.cs

@@ -10,7 +10,7 @@ namespace Avalonia.Data.Core.Plugins
     /// Handles binding to <see cref="IObservable{T}"/>s for the '^' stream binding operator.
     /// </summary>
     [UnconditionalSuppressMessage("Trimming", "IL3050", Justification = TrimmingMessages.IgnoreNativeAotSupressWarningMessage)]
-    public class ObservableStreamPlugin : IStreamPlugin
+    internal class ObservableStreamPlugin : IStreamPlugin
     {
         private static MethodInfo? s_observableGeneric;
         private static MethodInfo? s_observableSelect;

src/Avalonia.Base/Data/Core/Plugins/TaskStreamPlugin.cs

@@ -10,7 +10,7 @@ namespace Avalonia.Data.Core.Plugins
     /// Handles binding to <see cref="Task"/>s for the '^' stream binding operator.
     /// </summary>
     [UnconditionalSuppressMessage("Trimming", "IL3050", Justification = TrimmingMessages.IgnoreNativeAotSupressWarningMessage)]
-    public class TaskStreamPlugin : IStreamPlugin
+    internal class TaskStreamPlugin : IStreamPlugin
     {
         /// <summary>
         /// Checks whether this plugin handles the specified value.