Keep only InterfaceType(s) in resynthesized lists of interfaces and mixins.

pkg/analyzer/test/src/summary/resynthesize_test.dart

 // Copyright (c) 2015, 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 test.src.serialization.elements_test;
 
 import 'dart:convert';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/constant/value.dart';
@@ skipping 1704 matching lines @@
   }
 
   test_class_implicitField_setterFirst() {
     checkLibrary('class C { void set x(int value) {} int get x => 0; }');
   }
 
   test_class_interfaces() {
     checkLibrary('class C implements D, E {} class D {} class E {}');
   }
 
+  test_class_interfaces_unresolved() {
+    checkLibrary('class C implements X, Y, Z {} class X {} class Z {}',
+        allowErrors: true);
+  }
+
   test_class_method_abstract() {
     checkLibrary('abstract class C { f(); }');
   }
 
   test_class_method_external() {
     checkLibrary('class C { external f(); }');
   }
 
   test_class_method_params() {
     checkLibrary('class C { f(x, y) {} }');
   }
 
   test_class_method_static() {
     checkLibrary('class C { static f() {} }');
   }
 
   test_class_methods() {
     checkLibrary('class C { f() {} g() {} }');
   }
 
   test_class_mixins() {
     checkLibrary('class C extends Object with D, E {} class D {} class E {}');
   }
 
+  test_class_mixins_unresolved() {
+    checkLibrary('class C extends Object with X, Y, Z; class X {} class Z {}',
+        allowErrors: true);
+  }
+
   test_class_setter_abstract() {
     checkLibrary('abstract class C { void set x(int value); }');
   }
 
   test_class_setter_external() {
     checkLibrary('class C { external void set x(int value); }');
   }
 
   test_class_setter_implicit_param_type() {
     checkLibrary('class C { void set x(value) {} }');
@@ skipping 2908 matching lines @@
       fail('Unexpectedly tried to get unlinked summary for $uri');
     }
     return serializedUnit;
   }
 
   @override
   bool hasLibrarySummary(String uri) {
     return true;
   }
 }