remove IHighlightingDefinition2

src/AddIns/DisplayBindings/AvalonEdit.AddIn/Src/Options/NamedColorHighlightingItem.cs

@@ -134,10 +134,7 @@ namespace ICSharpCode.AvalonEdit.AddIn.Options
 		
 		IEnumerable<StringTagPair> GetXshdProperties()
 		{
-			IHighlightingDefinition2 def = ParentDefinition as IHighlightingDefinition2;
-			if (def == null)
-				yield break;
-			foreach (var p in def.Properties)
+			foreach (var p in ParentDefinition.Properties)
 				yield return new StringTagPair(p.Key, p.Value);
 		}
 		

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Highlighting/HighlightingManager.cs

@@ -20,7 +20,7 @@ namespace ICSharpCode.AvalonEdit.Highlighting
 	/// </remarks>
 	public class HighlightingManager : IHighlightingDefinitionReferenceResolver
 	{
-		sealed class DelayLoadedHighlightingDefinition : IHighlightingDefinition2
+		sealed class DelayLoadedHighlightingDefinition : IHighlightingDefinition
 		{
 			readonly object lockObj = new object();
 			readonly string name;
@@ -107,10 +107,7 @@ namespace ICSharpCode.AvalonEdit.Highlighting
 			
 			public IDictionary<string, string> Properties {
 				get {
-					var def = GetDefinition() as IHighlightingDefinition2;
-					if (def != null)
-						return def.Properties;
-					return null;
+					return GetDefinition().Properties;
 				}
 			}
 		}

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Highlighting/IHighlightingDefinition.cs

@@ -39,13 +39,7 @@ namespace ICSharpCode.AvalonEdit.Highlighting
 		/// Gets the list of named highlighting colors.
 		/// </summary>
 		IEnumerable<HighlightingColor> NamedHighlightingColors { get; }
-	}
 		
-	/// <summary>
-	/// Extension of IHighlightingDefinition to avoid breaking changes in the API.
-	/// </summary>
-	public interface IHighlightingDefinition2 : IHighlightingDefinition
-	{
 		/// <summary>
 		/// Gets the list of properties.
 		/// </summary>

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Highlighting/Xshd/XmlHighlightingDefinition.cs

@@ -13,7 +13,7 @@ using ICSharpCode.AvalonEdit.Utils;
 namespace ICSharpCode.AvalonEdit.Highlighting.Xshd
 {
 	[Serializable]
-	sealed class XmlHighlightingDefinition : IHighlightingDefinition2
+	sealed class XmlHighlightingDefinition : IHighlightingDefinition
 	{
 		public string Name { get; private set; }