Respect order dependencies in ImplicitConstructorBuilder.

pkg/analyzer/test/generated/non_error_resolver_test.dart

 // Copyright (c) 2014, 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.
 
 library engine.non_error_resolver_test;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
@@ skipping 1383 matching lines @@
 class A implements Function {
   noSuchMethod(inv) {
     return 42;
   }
 }''');
     resolve(source);
     assertNoErrors(source);
     verify([source]);
   }
 
+  void test_implicitConstructorDependencies() {
+    // No warning should be generated for the code below; this requires that
+    // implicit constructors are generated for C1 before C2, even though C1
+    // follows C2 in the file.  See dartbug.com/21600.
+    Source source = addSource(r'''
+class B {
+  B(int i);
+}
+class M1 {}
+class M2 {}
+
+class C2 = C1 with M2;
+class C1 = B with M1;
+
+main() {
+  new C2(5);
+}
+''');
+    resolve(source);
+    assertNoErrors(source);
+    verify([source]);
+  }
+
   void test_implicitThisReferenceInInitializer_constructorName() {
     Source source = addSource(r'''
 class A {
   A.named() {}
 }
 class B {
   var v;
   B() : v = new A.named();
 }''');
     resolve(source);
@@ skipping 3379 matching lines @@
     resolve(source);
     assertNoErrors(source);
     verify([source]);
     reset();
   }
 
   void _check_wrongNumberOfParametersForOperator1(String name) {
     _check_wrongNumberOfParametersForOperator(name, "a");
   }
 }