Fix initialization of IProject.TypeDefinitionModels.

src/AddIns/Debugger/Debugger.Core/TypeSystemExtensions.cs

@@ -436,12 +436,6 @@ namespace Debugger
 			return false;
 		}
 		
-		public static bool IsKnownType(this IType type, KnownTypeCode knownType)
-		{
-			var def = type.GetDefinition();
-			return def != null && def.KnownTypeCode == knownType;
-		}
-		
 		public static bool IsKnownType(this IType type, Type knownType)
 		{
 			var def = type.GetDefinition();

src/Main/Base/Project/Src/Project/CompilableProject.cs

@@ -372,8 +372,16 @@ namespace ICSharpCode.SharpDevelop.Project
 		public override ITypeDefinitionModelCollection TypeDefinitionModels {
 			get {
 				SD.MainThread.VerifyAccess();
-				if (typeDefinitionModels == null)
+				if (typeDefinitionModels == null) {
 					typeDefinitionModels = SD.GetRequiredService<IModelFactory>().CreateTopLevelTypeDefinitionCollection(new ProjectEntityModelContext(this, ".cs"));
+					var pc = ProjectContent;
+					if (pc != null) {
+						// Add the already loaded files into the model
+						foreach (var file in pc.Files) {
+							typeDefinitionModels.Update(null, file);
+						}
+					}
+				}
 				return typeDefinitionModels;
 			}
 		}

src/Main/Base/Project/Util/SharpDevelopExtensions.cs

@@ -465,7 +465,7 @@ namespace ICSharpCode.SharpDevelop
 		}
 		
 		/// <summary>
-		/// Retrieves the model instance the given unresolved entity.
+		/// Retrieves the model instance for the given unresolved entity.
 		/// </summary>
 		/// <param name="entity">The unresolved entity</param>
 		/// <param name="project">The project in which the entity is defined.