Change NotImplementedException to UnimplementedError.

tests/language/named_parameters_with_dollars_test.dart

Index: tests/language/named_parameters_with_dollars_test.dart
diff --git a/tests/language/named_parameters_with_dollars_test.dart b/tests/language/named_parameters_with_dollars_test.dart
index d1bc0f634c08cebb12880a0e3d9fd012a147e06f..6bd7af378ed4c7fcf3f42b6ec5fd661ac37d473d 100644
--- a/tests/language/named_parameters_with_dollars_test.dart
+++ b/tests/language/named_parameters_with_dollars_test.dart
@@ -37,8 +37,8 @@ format(thing) {
 makeTestClass(n) => [new TestClass(), new Decoy(), 'string'][n % 3];
 
 class Decoy {
-  method([a$b, b, a]) { throw const NotImplementedException(); }
-  psycho([$$$, $$, $])  { throw const NotImplementedException(); }
+  method([a$b, b, a]) { throw new UnimplementedError(); }
+  psycho([$$$, $$, $])  { throw new UnimplementedError(); }
 }
 
 testDollar() {