Remove unused flutter_run_test (#86828)

dev/automated_tests/flutter_run_test/flutter_run_test.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 'dart:io';
-
-import 'package:flutter_test/flutter_test.dart';
-
-void main() {
-  group('example', () {
-    test('passed', () {
-      print('This is print');
-      stderr.writeln('This is writeln');
-      expect(true, true);
-    });
-    test('failed', () {
-      expect(true, false);
-    });
-    test('skipped', () {
-      expect(true, false);
-    }, skip: true);
-  });
-}

dev/devicelab/bin/tasks/flutter_run_test.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 'dart:async';
-import 'dart:convert';
-import 'dart:io';
-
-import 'package:flutter_devicelab/common.dart';
-import 'package:flutter_devicelab/framework/devices.dart';
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/framework/task_result.dart';
-import 'package:flutter_devicelab/framework/utils.dart';
-import 'package:path/path.dart' as path;
-
-final Directory flutterGalleryDir = dir(path.join(flutterDirectory.path, 'examples/hello_world'));
-final File runTestSource = File(path.join(
-  flutterDirectory.path, 'dev', 'automated_tests', 'flutter_run_test', 'flutter_run_test.dart',
-));
-const Pattern passedMessageMatch = '+0: example passed';
-const Pattern failedMessageMatch = '+1: example failed [E]';
-const Pattern skippedMessageMatch = '+1 -1: example skipped';
-const Pattern finishedMessageMatch = '+1 ~1 -1: Some tests failed.';
-const Pattern printMessageMatch = 'This is print';
-const Pattern writelnMessageMatch = 'This is writeln';
-
-Future<void> main() async {
-  await task(createFlutterRunTask);
-}
-
-// verifies that the messages above are printed as a test script is executed.
-Future<TaskResult> createFlutterRunTask() async {
-  bool passedTest = false;
-  bool failedTest = false;
-  bool skippedTest = false;
-  bool finishedMessage = false;
-  bool printMessage = false;
-  bool writelnMessage = false;
-  final Device device = await devices.workingDevice;
-  await device.unlock();
-  final List<String> options = <String>[
-    '-t', runTestSource.absolute.path, '-d', device.deviceId, '-v', '--no-publish-port',
-  ];
-  await inDirectory<void>(flutterGalleryDir, () async {
-    final Process run = await startProcess(
-      path.join(flutterDirectory.path, 'bin', 'flutter'),
-      flutterCommandArgs('run', options),
-      environment: null,
-    );
-
-    final Completer<void> finished = Completer<void>();
-    final StreamSubscription<void> subscription = run.stdout
-        .transform<String>(utf8.decoder)
-        .transform<String>(const LineSplitter())
-        .listen((String line) {
-      print('stdout: $line');
-      // tests execute in order.
-      if (line.contains(passedMessageMatch)) {
-        passedTest = true;
-      } else if (line.contains(failedMessageMatch)) {
-        failedTest = true;
-      } else if (line.contains(skippedMessageMatch)) {
-        skippedTest = true;
-      } else if (line.contains(printMessageMatch)) {
-        printMessage = true;
-      } else if (line.contains(writelnMessageMatch)) {
-        writelnMessage = true;
-      } else if (line.contains(finishedMessageMatch)) {
-        finishedMessage = true;
-        finished.complete();
-      }
-    });
-    await finished.future.timeout(const Duration(minutes: 1));
-    unawaited(subscription.cancel());
-    run.kill();
-  });
-  return passedTest && failedTest && skippedTest && finishedMessage && printMessage && writelnMessage
-    ? TaskResult.success(<String, dynamic>{})
-    : TaskResult.failure('Test did not execute as expected.');
-}