Add missing coverage for generics properties of dynamic and void. Fix reflectType(dynamic) in dart2…

sdk/lib/_internal/lib/mirrors_patch.dart

Index: sdk/lib/_internal/lib/mirrors_patch.dart
diff --git a/sdk/lib/_internal/lib/mirrors_patch.dart b/sdk/lib/_internal/lib/mirrors_patch.dart
index 12547912ec604d13a164823797bedb1b24ed4ba2..b100937485d9fb9dad2ae6af43efd7bcb9eb665d 100644
--- a/sdk/lib/_internal/lib/mirrors_patch.dart
+++ b/sdk/lib/_internal/lib/mirrors_patch.dart
@@ -33,4 +33,9 @@ patch ClassMirror reflectClass(Type key) {
   return (tm as ClassMirror).originalDeclaration;
 }
 
-patch TypeMirror reflectType(Type key) => js.reflectType(key);
+patch TypeMirror reflectType(Type key) {
+  if (key == dynamic) {
+    return currentMirrorSystem().dynamicType;
+  }
+  return js.reflectType(key);
+}