Update unittest to new package layout.

tests/lib/mirrors/mirrors_test.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // 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.
 
-// TODO(rmacnak): Move the existing mirror tests here (a place for 
+// TODO(rmacnak): Move the existing mirror tests here (a place for
 // cross-implementation tests).
 
 #library("MirrorsTest.dart");
 #import("dart:mirrors");
-#import("../../../pkg/unittest/unittest.dart");
+#import("../../../pkg/unittest/lib/unittest.dart");
 
 var topLevelField;
 
 class Class {
   Class() { this.field = "default value"; }
   Class.withInitialValue(this.field);
   var field;
   static var staticField;
 }
 
 testFieldAccess(mirrors) {
   var instance = new Class();
 
   var libMirror = mirrors.libraries["MirrorsTest.dart"];
   var classMirror = libMirror.classes["Class"];
   var instMirror = reflect(instance);
 
   libMirror.setField('topLevelField', 42);
   var future = libMirror.getField('topLevelField');
   future.then(expectAsync1((resultMirror) {
     expect(resultMirror.reflectee, equals(42));
-    expect(topLevelField, equals(42));   
+    expect(topLevelField, equals(42));
   }));
-  
+
   classMirror.setField('staticField', 43);
   future = classMirror.getField('staticField');
   future.then(expectAsync1((resultMirror) {
     expect(resultMirror.reflectee, equals(43));
-    expect(Class.staticField, equals(43)); 
+    expect(Class.staticField, equals(43));
   }));
 
   instMirror.setField('field', 44);
   future = instMirror.getField('field');
   future.then(expectAsync1((resultMirror) {
     expect(resultMirror.reflectee, equals(44));
-    expect(instance.field, equals(44)); 
+    expect(instance.field, equals(44));
   }));
 }
 
 testClosureMirrors(mirrors) {
   var closure = (x, y, z) { return x + y + z; };
-  
+
   var mirror = reflect(closure);
   expect(mirror is ClosureMirror, equals(true));
-  
+
   var funcMirror = mirror.function;
   expect(funcMirror is MethodMirror, equals(true));
   expect(funcMirror.parameters.length, equals(3));
 
   var future = mirror.apply([2, 4, 8]);
   future.then(expectAsync1((resultMirror) {
     expect(resultMirror.reflectee, equals(14));
   }));
 }
 
 testInvokeConstructor(mirrors) {
   var libMirror = mirrors.libraries["MirrorsTest.dart"];
   var classMirror = libMirror.classes["Class"];
-  
+
   var future = classMirror.newInstance('', []);
   future.then(expectAsync1((resultMirror) {
     var instance = resultMirror.reflectee;
     expect(instance is Class, equals(true));
     expect(instance.field, equals("default value"));
   }));
 
   future = classMirror.newInstance('withInitialValue', [45]);
   future.then(expectAsync1((resultMirror) {
     var instance = resultMirror.reflectee;
     expect(instance is Class, equals(true));
     expect(instance.field, equals(45));
   }));
 }
 
 main() {
   var mirrors = currentMirrorSystem();
 
   test("Test field access", () { testFieldAccess(mirrors); });
   test("Test closure mirrors", () { testClosureMirrors(mirrors); });
   test("Test invoke constructor", () { testInvokeConstructor(mirrors); });
 }