Use the runtime for generic subsitution of variable types, return types, parameter types.

runtime/lib/mirrors_impl.dart

Index: runtime/lib/mirrors_impl.dart
diff --git a/runtime/lib/mirrors_impl.dart b/runtime/lib/mirrors_impl.dart
index a2ab082698353683625dd7195acd806f3046f56c..d794db09be193aa9fdeec37c9d395b6892ab9f1c 100644
--- a/runtime/lib/mirrors_impl.dart
+++ b/runtime/lib/mirrors_impl.dart
@@ -1208,15 +1208,17 @@ class _LocalMethodMirrorImpl extends _LocalDeclarationMirrorImpl
     throw new UnimplementedError('MethodMirror.location is not implemented');
   }
 
+  Type get _instantiator => owner is ClassMirror ? owner._reflectedType : null;
+
   TypeMirror _returnType = null;
   TypeMirror get returnType {
     if (_returnType == null) {
       if (isConstructor) {
         _returnType = owner;

[regis, 2013/11/06 19:06:07]

Why don't you instantiate in this case?

       } else {
-        _returnType = reflectType(_MethodMirror_return_type(_reflectee));
+        _returnType = reflectType(
+            _MethodMirror_return_type(_reflectee, _instantiator));
       }
-      _returnType = _returnType._instantiateInContextOf(owner);
     }
     return _returnType;
   }
@@ -1276,7 +1278,7 @@ class _LocalMethodMirrorImpl extends _LocalDeclarationMirrorImpl
   static dynamic _MethodMirror_owner(reflectee)
       native "MethodMirror_owner";
 
-  static dynamic _MethodMirror_return_type(reflectee)
+  static dynamic _MethodMirror_return_type(reflectee, instantiator)
       native "MethodMirror_return_type";
 
   List<ParameterMirror> _MethodMirror_parameters(reflectee)
@@ -1308,18 +1310,19 @@ class _LocalVariableMirrorImpl extends _LocalDeclarationMirrorImpl
     throw new UnimplementedError('VariableMirror.location is not implemented');
   }
 
+  Type get _instantiator => owner is ClassMirror ? owner._reflectedType : null;
+
   TypeMirror _type;
   TypeMirror get type {
     if (_type == null) {
-       _type = reflectType(_VariableMirror_type(_reflectee));
-       _type = _type._instantiateInContextOf(owner);
+       _type = reflectType(_VariableMirror_type(_reflectee, _instantiator));
     }
     return _type;
   }
 
   String toString() => "VariableMirror on '${MirrorSystem.getName(simpleName)}'";
 
-  static _VariableMirror_type(reflectee)
+  static _VariableMirror_type(reflectee, instantiator)
       native "VariableMirror_type";
 }
 
@@ -1361,22 +1364,26 @@ class _LocalParameterMirrorImpl extends _LocalVariableMirrorImpl
   bool get hasDefaultValue => _defaultValueReflectee != null;
 
   List<InstanceMirror> get metadata {
-    if ( _unmirroredMetadata == null) return emptyList;
+    if (_unmirroredMetadata == null) return emptyList;
     return new UnmodifiableListView(_unmirroredMetadata.map(reflect));
   }
 
+  Type get _instantiator {
+    return owner.owner is ClassMirror ? owner.owner._reflectedType : null;
+  }
+
   TypeMirror _type = null;
   TypeMirror get type {
     if (_type == null) {
-      _type = reflectType(_ParameterMirror_type(_reflectee, _position));
-      _type = _type._instantiateInContextOf(owner);
+      _type = reflectType(
+          _ParameterMirror_type(_reflectee, _position, _instantiator));
     }
     return _type;
   }
 
   String toString() => "ParameterMirror on '${_n(simpleName)}'";
 
-  static Type _ParameterMirror_type(_reflectee, _position)
+  static Type _ParameterMirror_type(_reflectee, _position, instantiator)
       native "ParameterMirror_type";
 }