Fix resynthesis tests after dead code detection improvements.

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 3634 matching lines @@
 
   test_localFunctions_inTopLevelGetter() {
     checkLibrary(r'''
 get g {
   f() {}
 }
 ''');
   }
 
   test_localLabels_inConstructor() {
-    checkLibrary(r'''
+    checkLibrary(
+        r'''
 class C {
   C() {
     aaa: while (true) {}
     bbb: switch (42) {
       ccc: case 0:
         break;
     }
   }
 }
-''');
+''',
+        allowErrors: true);
   }
 
   test_localLabels_inMethod() {
-    checkLibrary(r'''
+    checkLibrary(
+        r'''
 class C {
   m() {
     aaa: while (true) {}
     bbb: switch (42) {
       ccc: case 0:
         break;
     }
   }
 }
-''');
+''',
+        allowErrors: true);
   }
 
   test_localLabels_inTopLevelFunction() {
-    checkLibrary(r'''
+    checkLibrary(
+        r'''
 main() {
   aaa: while (true) {}
   bbb: switch (42) {
     ccc: case 0:
       break;
   }
 }
-''');
+''',
+        allowErrors: true);
   }
 
   test_localVariables_inConstructor() {
     checkLibrary(r'''
 class C {
   C() {
     int v;
     f() {}
   }
 }
@@ skipping 900 matching lines @@
       fail('Unexpectedly tried to get unlinked summary for $uri');
     }
     return serializedUnit;
   }
 
   @override
   bool hasLibrarySummary(String uri) {
     return true;
   }
 }