Add TypeVariable object on runtime to support reflection on type variables.

tests/lib/mirrors/class_mirror_type_variables_test.dart

Index: tests/lib/mirrors/class_mirror_type_variables_test.dart
diff --git a/tests/lib/mirrors/class_mirror_type_variables_test.dart b/tests/lib/mirrors/class_mirror_type_variables_test.dart
index ee7baf95b8def14d0b03a87d9c43dd527904cea4..2a3ea7ef7a47a2d250029d27b0d313f91c3bcfb4 100644
--- a/tests/lib/mirrors/class_mirror_type_variables_test.dart
+++ b/tests/lib/mirrors/class_mirror_type_variables_test.dart
@@ -6,15 +6,44 @@ import "dart:mirrors";
 
 import "package:expect/expect.dart";
 
+class NoTypeParams {}
+class A<T, S extends String> {}
+class B<Z extends B<Z>> {}
 class C<R,S,T> {
   R foo(R r) => r;
   S bar(S s) => s;
   T baz(T t) => t;
 }
 
-class NoTypeParams {}
+testNoTypeParams() {
+  ClassMirror cm = reflectClass(NoTypeParams);
+  Expect.equals(cm.typeVariables.length, 0);
+}
 
-main() {
+void testA() {
+  ClassMirror a = reflectClass(A);
+  Expect.equals(2, a.typeVariables.length);
+
+  TypeVariableMirror aT = a.typeVariables[0];
+  TypeVariableMirror aS = a.typeVariables[1];
+  TypeMirror aTBound = aT.upperBound.originalDeclaration;
+  TypeMirror aSBound = aS.upperBound.originalDeclaration;
+
+  Expect.equals(reflectClass(Object), aTBound);
+  Expect.equals(reflectClass(String), aSBound);
+}
+
+void testB() {
+  ClassMirror b = reflectClass(B);
+  Expect.equals(1, b.typeVariables.length);
+
+  TypeVariableMirror bZ = b.typeVariables[0];
+  ClassMirror bZBound = bZ.upperBound.originalDeclaration;
+  Expect.equals(b, bZBound);
+  Expect.equals(bZ, bZBound.typeVariables[0]);
+}
+
+testC() {
   ClassMirror cm;
   cm = reflectClass(C);
   Expect.equals(3, cm.typeVariables.length);
@@ -25,6 +54,11 @@ main() {
   Expect.equals(#R, values.elementAt(0).simpleName);
   Expect.equals(#S, values.elementAt(1).simpleName);
   Expect.equals(#T, values.elementAt(2).simpleName);
-  cm = reflectClass(NoTypeParams);
-  Expect.equals(cm.typeVariables.length, 0);
 }
+
+main() {
+  testNoTypeParams();
+  testA();
+  testB();
+  testC();
+}