Extend Future.then inference to subclasses

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

Index: pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
diff --git a/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart b/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
index bca50680f91b3ad1563ded74aa2007a448c89059..bd2c1fbf038026f1718c02093cf038acf81bac0a 100644
--- a/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
+++ b/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
@@ -209,6 +209,36 @@ class AstInferredTypeTest extends AbstractResynthesizeTest
 
   @override
   @failingTest
+  void test_futureThen() {
+    super.test_futureThen();
+  }
+
+  @override
+  @failingTest
+  void test_futureThen_conditional() {
+    super.test_futureThen_conditional();
+  }
+
+  @override
+  @failingTest
+  void test_futureThen_upwards() {
+    super.test_futureThen_upwards();
+  }
+
+  @override
+  @failingTest
+  void test_futureUnion_asyncConditional() {
+    super.test_futureUnion_asyncConditional();
+  }
+
+  @override
+  @failingTest
+  void test_futureUnion_downwards() {
+    super.test_futureUnion_downwards();
+  }
+
+  @override
+  @failingTest
   void test_genericMethods_inferJSBuiltin() {
     super.test_genericMethods_inferJSBuiltin();
   }