Fix AST-based type inference via interfaces.

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

 // Copyright (c) 2016, 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 analyzer.test.src.summary.resynthesize_ast_test;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/generated/engine.dart'
@@ skipping 493 matching lines @@
   void test_inferCorrectlyOnMultipleVariablesDeclaredTogether() {
     super.test_inferCorrectlyOnMultipleVariablesDeclaredTogether();
   }
 
   @override
   @failingTest
   void test_inferenceInCyclesIsDeterministic() {
     super.test_inferenceInCyclesIsDeterministic();
   }
 
+  @override
+  @failingTest
+  void test_inferredType_opAssignToProperty_prefixedIdentifier() {
+    super.test_inferredType_opAssignToProperty_prefixedIdentifier();
+  }
+
+  @override
+  @failingTest
+  void test_inferredType_opAssignToProperty_prefixedIdentifier_viaInterface() {
+    super
+        .test_inferredType_opAssignToProperty_prefixedIdentifier_viaInterface();
+  }
+
   void test_invokeMethod_notGeneric_genericClass() {
     var unit = checkFile(r'''
 class C<T> {
   T m(int a, {String b, T c}) => null;
 }
 var v = new C<double>().m(1, b: 'bbb', c: 2.0);
   ''');
     expect(unit.topLevelVariables[0].type.toString(), 'double');
   }
 
@@ skipping 155 matching lines @@
     }
 
     UnlinkedUnit definingUnit = _getUnlinkedUnit(librarySource);
     LinkedLibraryBuilder linkedLibrary =
         prelink(definingUnit, getPart, getImport);
     linkedLibrary.dependencies.skip(1).forEach((LinkedDependency d) {
       _serializeLibrary(resolveRelativeUri(d.uri));
     });
   }
 }