Stop running pub get at gclient sync time and fix build bugs

mojo/public/dart/third_party/shelf_static/test/test_all.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 shelf_static.test_all;
+
+import 'package:scheduled_test/scheduled_test.dart';
+
+import 'alternative_root_test.dart' as alternative_root;
+import 'basic_file_test.dart' as basic_file;
+import 'default_document_test.dart' as default_document;
+import 'directory_listing_test.dart' as directory_listing;
+import 'get_handler_test.dart' as get_handler;
+import 'sample_test.dart' as sample;
+import 'symbolic_link_test.dart' as symbolic_link;
+
+void main() {
+  group('alternative_root', alternative_root.main);
+  group('basic_file', basic_file.main);
+  group('default_document', default_document.main);
+  group('directory_listing', directory_listing.main);
+  group('get_handler', get_handler.main);
+  group('sample', sample.main);
+  group('symbolic_link', symbolic_link.main);
+}