[ci] remove create offline tests (#65791)

Currently these tests are taking CI time without providing any value, because there is no verification that network connectivity is avoided. This is better covered by a unit test that verifies that --offline is passed to pub.

dev/bots/test.dart

@@ -1239,9 +1239,6 @@ Future<void> _runHostOnlyDeviceLabTests() async {
   final List<ShardRunner> tests = <ShardRunner>[
     // Keep this in alphabetical order.
     () => _runDevicelabTest('build_aar_module_test', environment: gradleEnvironment),
-    if (Platform.isMacOS) () => _runDevicelabTest('flutter_create_offline_test_mac'),
-    if (Platform.isLinux) () => _runDevicelabTest('flutter_create_offline_test_linux'),
-    if (Platform.isWindows) () => _runDevicelabTest('flutter_create_offline_test_windows'),
     () => _runDevicelabTest('gradle_fast_start_test', environment: gradleEnvironment),
     // TODO(ianh): Fails on macOS looking for "dexdump", https://github.com/flutter/flutter/issues/42494
     if (!Platform.isMacOS) () => _runDevicelabTest('gradle_jetifier_test', environment: gradleEnvironment),
@@ -1251,12 +1248,10 @@ Future<void> _runHostOnlyDeviceLabTests() async {
     () => _runDevicelabTest('gradle_plugin_fat_apk_test', environment: gradleEnvironment),
     () => _runDevicelabTest('gradle_plugin_light_apk_test', environment: gradleEnvironment),
     () => _runDevicelabTest('gradle_r8_test', environment: gradleEnvironment),
-
     () => _runDevicelabTest('module_host_with_custom_build_test', environment: gradleEnvironment, testEmbeddingV2: true),
     () => _runDevicelabTest('module_custom_host_app_name_test', environment: gradleEnvironment),
     () => _runDevicelabTest('module_test', environment: gradleEnvironment, testEmbeddingV2: true),
     () => _runDevicelabTest('plugin_dependencies_test', environment: gradleEnvironment),
-
     if (Platform.isMacOS) () => _runDevicelabTest('module_test_ios'),
     if (Platform.isMacOS) () => _runDevicelabTest('build_ios_framework_module_test'),
     if (Platform.isMacOS) () => _runDevicelabTest('plugin_lint_mac'),

dev/devicelab/bin/tasks/flutter_create_offline_test_linux.dart

-// Copyright 2014 The Flutter Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/tasks/integration_tests.dart';
-
-Future<void> main() async {
-  await task(createFlutterCreateOfflineTest());
-}

dev/devicelab/bin/tasks/flutter_create_offline_test_mac.dart

-// Copyright 2014 The Flutter Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/tasks/integration_tests.dart';
-
-Future<void> main() async {
-  await task(createFlutterCreateOfflineTest());
-}

dev/devicelab/bin/tasks/flutter_create_offline_test_windows.dart

-// Copyright 2014 The Flutter Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/tasks/integration_tests.dart';
-
-Future<void> main() async {
-  await task(createFlutterCreateOfflineTest());
-}

dev/devicelab/lib/tasks/integration_tests.dart

@@ -3,9 +3,7 @@
 // found in the LICENSE file.
 
 import 'dart:async';
-import 'dart:io';
 
-import 'package:path/path.dart' as path;
 import '../framework/adb.dart';
 import '../framework/framework.dart';
 import '../framework/utils.dart';
@@ -88,34 +86,6 @@ TaskFunction createImageLoadingIntegrationTest() {
   );
 }
 
-TaskFunction createFlutterCreateOfflineTest() {
-  return () async {
-    final Directory tempDir = Directory.systemTemp.createTempSync('flutter_create_test.');
-    String output;
-    // The default create template has an actual online dependency against
-    // a pub package. Make sure it's available in pub cache first before
-    // trying to resolve it offline.
-    await inDirectory(tempDir, () async {
-      output = await eval(
-        path.join(flutterDirectory.path, 'bin', 'flutter'),
-        <String>['pub', 'cache', 'add', 'cupertino_icons', '--version', '1.0.0'],
-      );
-    });
-    await inDirectory(tempDir, () async {
-      output = await eval(
-        path.join(flutterDirectory.path, 'bin', 'flutter'),
-        <String>['create', '--offline', 'flutter_create_test'],
-      );
-    });
-    if (output.contains(RegExp('building flutter tool', caseSensitive: false))) {
-      return TaskResult.failure('`flutter create --offline` should not rebuild flutter tool');
-    } else if (!output.contains('All done!')) {
-      return TaskResult.failure('`flutter create` failed');
-    }
-    return TaskResult.success(null);
-  };
-}
-
 TaskFunction createAndroidSplashScreenKitchenSinkTest() {
   return DriverTest(
     '${flutterDirectory.path}/dev/integration_tests/android_splash_screens/splash_screen_kitchen_sink',