Use FlushTargetFilter to pre-filter targets before checking their results.

pkg/analyzer/test/src/context/context_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 analyzer.test.src.context.context_test;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 1104 matching lines @@
   void test_flushResolvedUnit_updateFile_dontNotify() {
     String oldCode = '';
     String newCode = r'''
 import 'dart:async';
 ''';
     String path = '/test.dart';
     Source source = resourceProvider.newFile(path, oldCode).createSource();
     context.applyChanges(new ChangeSet()..addedSource(source));
     context.resolveCompilationUnit2(source, source);
     // Flush all results units.
-    context.analysisCache.flush((target, result) {
+    context.analysisCache.flush((target) => true, (target, result) {
       if (target.source == source) {
         return RESOLVED_UNIT_RESULTS.contains(result);
       }
       return false;
     });
     // Update the file, but don't notify the context.
     resourceProvider.updateFile(path, newCode);
     // Driver must detect that the file was changed and recover.
     CompilationUnit unit = context.resolveCompilationUnit2(source, source);
     expect(unit, isNotNull);
   }
 
   void test_flushResolvedUnit_updateFile_dontNotify2() {
     String oldCode = r'''
 main() {}
 ''';
     String newCode = r'''
 import 'dart:async';
 main() {}
 ''';
     String path = '/test.dart';
     Source source = resourceProvider.newFile(path, oldCode).createSource();
     context.applyChanges(new ChangeSet()..addedSource(source));
     context.resolveCompilationUnit2(source, source);
     // Flush all results units.
-    context.analysisCache.flush((target, result) {
+    context.analysisCache.flush((target) => true, (target, result) {
       if (target.source == source) {
         if (target.source == source) {
           return RESOLVED_UNIT_RESULTS.contains(result);
         }
       }
       return false;
     });
     // Update the file, but don't notify the context.
     resourceProvider.updateFile(path, newCode);
     // Driver must detect that the file was changed and recover.
@@ skipping 4088 matching lines @@
    * Initialize the visitor.
    */
   _ElementGatherer();
 
   @override
   void visitElement(Element element) {
     elements[element] = element;
     super.visitElement(element);
   }
 }