Add smoke tests to test every commit on a Catalina host. (#38567)

* Add a smoke test to test every commit on a Catalina host.
* Also add a hot-reload test.

Related issue: #36290.

dev/devicelab/bin/tasks/smoke_catalina_start_up.dart

+// Copyright 2019 The Chromium 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 'package:flutter_devicelab/tasks/perf_tests.dart';
+import 'package:flutter_devicelab/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+
+Future<void> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.ios;
+  // It's intended to use the Gallery startup test as a smoke test on macOS
+  // Catalina.
+  await task(createFlutterGalleryStartupTest());
+}

dev/devicelab/manifest.yaml

@@ -510,6 +510,20 @@ tasks:
     stage: devicelab_ios
     required_agent_capabilities: ["mac/ios"]
 
+  smoke_catalina_start_up:
+    description: >
+      A smoke test that runs on macOS Catalina, which is a clone of the Gallery startup latency test.
+    stage: devicelab_ios
+    flaky: true
+    required_agent_capabilities: ["mac-catalina/ios"]
+
+  smoke_catalina_hot_mode_dev_cycle__benchmark:
+    description: >
+      A some test that runs on macOS Catalina, which is a clone of the Dart VM hot patching performance benchmarking.
+    stage: devicelab_ios
+    flaky: true
+    required_agent_capabilities: ["mac-catalina/ios"]
+
   # Tests running on Windows host
 
   flavors_test_win:

dev/devicelab/smoke_catalina_hot_mode_dev_cycle__benchmark.dart

+// Copyright (c) 2019 The Chromium 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 'package:flutter_devicelab/tasks/hot_mode_tests.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+
+Future<void> main() async {
+  await task(createHotModeTest());
+}