remove docgen source and targets from build

pkg/docgen/test/util.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 docgen.test.util;
-
-import 'dart:convert';
-import 'dart:io';
-import 'package:path/path.dart' as p;
-import 'package:scheduled_test/descriptor.dart' as d;
-import 'package:scheduled_test/scheduled_test.dart';
-
-void scheduleTempDir() {
-  var tempDir;
-  schedule(() {
-    return Directory.systemTemp
-        .createTemp('docgen_test-')
-        .then((dir) {
-      tempDir = dir;
-      d.defaultRoot = tempDir.path;
-    });
-  });
-
-  currentSchedule.onComplete.schedule(() {
-    d.defaultRoot = null;
-    return tempDir.delete(recursive: true);
-  });
-}
-
-String getMultiLibraryCodePath() {
-  var currentScript = p.fromUri(Platform.script);
-  var codeDir = p.join(p.dirname(currentScript), 'multi_library_code');
-
-  assert(FileSystemEntity.isDirectorySync(codeDir));
-
-  return codeDir;
-}
-
-final Matcher hasSortedLines = predicate((String input) {
-  var lines = new LineSplitter().convert(input);
-
-  var sortedLines = new List.from(lines)..sort();
-
-  var orderedMatcher = orderedEquals(sortedLines);
-  return orderedMatcher.matches(lines, {});
-}, 'String has sorted lines');
-
-final Matcher isJsonMap = predicate((input) {
-  try {
-    return JSON.decode(input) is Map;
-  } catch (e) {
-    return false;
-  }
-}, 'Output is JSON encoded Map');