Move flat_buffer and api_signature into front_end.

pkg/analyzer/test/src/summary/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 test.src.serialization.test_all;
 
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
-import 'api_signature_test.dart' as api_signature_test;
-import 'flat_buffers_test.dart' as flat_buffers_test;
 import 'in_summary_source_test.dart' as in_summary_source_test;
 import 'linker_test.dart' as linker_test;
 import 'name_filter_test.dart' as name_filter_test;
 import 'package_bundle_reader_test.dart' as package_bundle_reader_test;
 import 'prelinker_test.dart' as prelinker_test;
 import 'resynthesize_ast_test.dart' as resynthesize_ast_test;
 import 'summarize_ast_strong_test.dart' as summarize_ast_strong_test;
 import 'summarize_ast_test.dart' as summarize_ast_test;
 import 'top_level_inference_test.dart' as top_level_inference_test;
 
 /// Utility for manually running all tests.
 main() {
   defineReflectiveSuite(() {
-    api_signature_test.main();
-    flat_buffers_test.main();
     in_summary_source_test.main();
     linker_test.main();
     name_filter_test.main();
     package_bundle_reader_test.main();
     prelinker_test.main();
     resynthesize_ast_test.main();
     summarize_ast_strong_test.main();
     summarize_ast_test.main();
     top_level_inference_test.main();
   }, name: 'summary');
 }