[benchmarks] Add time to development benchmark for Android (#46717)

dev/devicelab/bin/tasks/time_to_development_benchmark__android.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_devicelab/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/framework/utils.dart';
+import 'package:path/path.dart' as path;
+
+Future<void> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.android;
+  await task(createTimeToDevelopmentCommand);
+}
+
+final Directory flutterGalleryDir =
+    dir(path.join(flutterDirectory.path, 'examples', 'flutter_gallery'));
+final Directory editedFlutterGalleryDir =
+    dir(path.join(Directory.systemTemp.path, 'edited_flutter_gallery'));
+
+Future<TaskResult> createTimeToDevelopmentCommand() async {
+  final Map<String, double> allResults = <String, double>{};
+  bool failed = false;
+  await inDirectory<void>(flutterDirectory, () async {
+    rmTree(editedFlutterGalleryDir);
+    mkdirs(editedFlutterGalleryDir);
+    recursiveCopy(flutterGalleryDir, editedFlutterGalleryDir);
+    await inDirectory<void>(editedFlutterGalleryDir, () async {
+      final Device device = await devices.workingDevice;
+      await device.unlock();
+      final Stopwatch stopwatch = Stopwatch()..start();
+      final Process initialBuild = await startProcess(
+        path.join(flutterDirectory.path, 'bin', 'flutter'),
+        <String>['run', '--debug', '-d', device.deviceId, '--no-resident',],
+      );
+      int exitCode = await initialBuild.exitCode;
+      if (exitCode != 0) {
+        failed = true;
+        return;
+      }
+      final int initialBuildMilliseconds = stopwatch.elapsedMilliseconds;
+      stopwatch
+        ..reset()
+        ..start();
+      // Update a source file.
+      final File appDartSource = file(path.join(
+        editedFlutterGalleryDir.path,
+        'lib/gallery/app.dart',
+      ));
+      appDartSource.writeAsStringSync(
+        appDartSource.readAsStringSync().replaceFirst(
+          "'Flutter Gallery'",
+          "'Updated Flutter Gallery'",
+        ),
+      );
+
+      final Process secondBuild = await startProcess(
+        path.join(flutterDirectory.path, 'bin', 'flutter'),
+        <String>['run', '--debug', '-d', device.deviceId, '--no-resident'],
+        environment: null,
+      );
+      exitCode = await secondBuild.exitCode;
+      if (exitCode != 0) {
+        failed = true;
+        return;
+      }
+      stopwatch.stop();
+      allResults['time_to_development'] = initialBuildMilliseconds.toDouble();
+      allResults['time_to_development_incremental'] =
+          stopwatch.elapsedMilliseconds.toDouble();
+    });
+  });
+  if (failed) {
+    return TaskResult.failure('Failed to build debug app');
+  }
+
+  return TaskResult.success(allResults,
+      benchmarkScoreKeys: allResults.keys.toList());
+}

dev/devicelab/manifest.yaml

@@ -382,6 +382,12 @@ tasks:
     stage: devicelab
     required_agent_capabilities: ["linux/android"]
 
+  time_to_development_benchmark__android:
+    description: >
+      Measures time from flutter run until resident runner setup is complete.
+    stage: devicelab
+    required_agent_capabilities: ["linux/android"]
+
   # iOS on-device tests
 
   tiles_scroll_perf_ios__timeline_summary: