Remove PrintWriter and PrintStringWriter from java_core.

pkg/analyzer/test/src/dart/ast/utilities_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.dart.ast.utilities_test;
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
 import 'package:analyzer/src/dart/element/element.dart';
-import 'package:analyzer/src/generated/java_core.dart';
 import 'package:analyzer/src/generated/java_engine.dart' show Predicate;
 import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/testing/ast_factory.dart';
 import 'package:analyzer/src/generated/testing/element_factory.dart';
 import 'package:analyzer/src/generated/testing/token_factory.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 import 'package:unittest/unittest.dart';
 
 import '../../../generated/parser_test.dart' show ParserTestCase;
 import '../../../generated/test_support.dart';
@@ skipping 3310 matching lines @@
 
   /**
    * Assert that a `ToSourceVisitor` will produce the expected source when visiting the given
    * node.
    *
    * @param expectedSource the source string that the visitor is expected to produce
    * @param node the AST node being visited to produce the actual source
    * @throws AFE if the visitor does not produce the expected source for the given node
    */
   void _assertSource(String expectedSource, AstNode node) {
-    PrintStringWriter writer = new PrintStringWriter();
-    node.accept(new ToSourceVisitor(writer));
-    expect(writer.toString(), expectedSource);
+    StringBuffer buffer = new StringBuffer();
+    node.accept(new ToSourceVisitor(buffer));
+    expect(buffer.toString(), expectedSource);
   }
 }