Revert "Remove Expect from core library."

tests/compiler/dart2js_native/native_call_arity3_frog_test.dart

Index: tests/compiler/dart2js_native/native_call_arity3_frog_test.dart
diff --git a/tests/compiler/dart2js_native/native_call_arity3_frog_test.dart b/tests/compiler/dart2js_native/native_call_arity3_frog_test.dart
index ff59e315593e3a07434232ba417eee05061ed2e1..8a45c058ff5d1a680ebe229bb45d9abae2f56915 100644
--- a/tests/compiler/dart2js_native/native_call_arity3_frog_test.dart
+++ b/tests/compiler/dart2js_native/native_call_arity3_frog_test.dart
@@ -2,8 +2,6 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import "package:expect/expect.dart";
-
 // Test similar to NativeCallArity1FrogTest, but with default values to
 // parameters set to null. These parameters should be treated as if they
 // do not have a default value for the native methods.