fix microbenchmarks on iOS (#7429)

dev/benchmarks/microbenchmarks/lib/stocks/animation_bench.dart

@@ -2,6 +2,7 @@
 // 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:io';
 
 import 'package:flutter_test/flutter_test.dart';

dev/benchmarks/microbenchmarks/lib/stocks/build_bench.dart

+import 'dart:async';
 import 'dart:io';
 
 import 'package:flutter_test/flutter_test.dart';
@@ -20,6 +21,7 @@ Future<Null> main() async {
   await benchmarkWidgets((WidgetTester tester) async {
     stocks.main();
     await tester.pump(); // Start startup animation
+    new Timer(const Duration(milliseconds: 1100), () { });  // workaround for https://github.com/flutter/flutter/issues/7433
     await tester.pump(const Duration(seconds: 1)); // Complete startup animation
     await tester.tapAt(new Point(20.0, 20.0)); // Open drawer
     await tester.pump(); // Start drawer animation

dev/benchmarks/microbenchmarks/lib/stocks/layout_bench.dart

+import 'dart:async';
 import 'dart:io';
 
 import 'package:flutter_test/flutter_test.dart';
@@ -19,6 +20,7 @@ Future<Null> main() async {
   await benchmarkWidgets((WidgetTester tester) async {
     stocks.main();
     await tester.pump(); // Start startup animation
+    new Timer(const Duration(milliseconds: 1100), () { });  // workaround for https://github.com/flutter/flutter/issues/7433
     await tester.pump(const Duration(seconds: 1)); // Complete startup animation
     await tester.tapAt(new Point(20.0, 20.0)); // Open drawer
     await tester.pump(); // Start drawer animation

dev/devicelab/bin/tasks/microbenchmarks.dart

@@ -3,88 +3,13 @@
 // found in the LICENSE file.
 
 import 'dart:async';
-import 'dart:convert';
-import 'dart:io';
-
-import 'package:path/path.dart' as path;
 
 import 'package:flutter_devicelab/framework/adb.dart';
 import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/framework/utils.dart';
+import 'package:flutter_devicelab/tasks/microbenchmarks.dart';
 
-/// Runs benchmarks in `dev/benchmarks/microbenchmarks` in the device lab and
-/// reports results to the dashboard.
+/// Runs microbenchmarks on Android.
 Future<Null> main() async {
-  await task(() async {
-    Device device = await devices.workingDevice;
-    await device.unlock();
-
-    Future<Map<String, double>> _runMicrobench(String benchmarkPath) async {
-      print('Running $benchmarkPath');
-      Directory appDir = dir(path.join(flutterDirectory.path, 'dev/benchmarks/microbenchmarks'));
-      Process flutterProcess = await inDirectory(appDir, () async {
-        return await _startFlutter(
-          options: <String>[
-            '--release',
-            '-d',
-            device.deviceId,
-            benchmarkPath,
-          ],
-          canFail: false,
-        );
-      });
-
-      return await _readJsonResults(flutterProcess);
-    }
-
-    Map<String, double> allResults = <String, double>{};
-    allResults.addAll(await _runMicrobench('lib/stocks/layout_bench.dart'));
-    allResults.addAll(await _runMicrobench('lib/stocks/build_bench.dart'));
-    allResults.addAll(await _runMicrobench('lib/stocks/animation_bench.dart'));
-    allResults.addAll(await _runMicrobench('lib/gestures/velocity_tracker_bench.dart'));
-
-    return new TaskResult.success(allResults, benchmarkScoreKeys: allResults.keys.toList());
-  });
-}
-
-Future<Process> _startFlutter({String command = 'run', List<String> options: const <String>[], bool canFail: false, Map<String, String> env}) {
-  List<String> args = <String>['run']..addAll(options);
-  return startProcess(path.join(flutterDirectory.path, 'bin', 'flutter'), args, env: env);
-}
-
-Future<Map<String, double>> _readJsonResults(Process process) {
-  // IMPORTANT: keep these values in sync with dev/benchmarks/microbenchmarks/lib/common.dart
-  const String jsonStart = '================ RESULTS ================';
-  const String jsonEnd = '================ FORMATTED ==============';
-  bool jsonStarted = false;
-  StringBuffer jsonBuf = new StringBuffer();
-  Completer<Map<String, double>> completer = new Completer<Map<String, double>>();
-  StreamSubscription<String> stdoutSub;
-
-  int prefixLength = 0;
-  stdoutSub = process.stdout
-      .transform(const Utf8Decoder())
-      .transform(const LineSplitter())
-      .listen((String line) {
-    print(line);
-
-    if (line.contains(jsonStart)) {
-      jsonStarted = true;
-      prefixLength = line.indexOf(jsonStart);
-      return;
-    }
-
-    if (line.contains(jsonEnd)) {
-      jsonStarted = false;
-      stdoutSub.cancel();
-      process.kill(ProcessSignal.SIGINT);  // flutter run doesn't quit automatically
-      completer.complete(JSON.decode(jsonBuf.toString()));
-      return;
-    }
-
-    if (jsonStarted)
-      jsonBuf.writeln(line.substring(prefixLength));
-  });
-
-  return completer.future;
+  deviceOperatingSystem = DeviceOperatingSystem.android;
+  await task(createMicrobenchmarkTask());
 }

dev/devicelab/bin/tasks/microbenchmarks_ios.dart

+// Copyright 2017 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/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/tasks/microbenchmarks.dart';
+
+/// Runs microbenchmarks on iOS.
+Future<Null> main() async {
+  deviceOperatingSystem = DeviceOperatingSystem.ios;
+  await task(createMicrobenchmarkTask());
+}

dev/devicelab/lib/tasks/microbenchmarks.dart

+// Copyright 2017 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 'dart:convert';
+import 'dart:io';
+
+import 'package:path/path.dart' as path;
+
+import 'package:flutter_devicelab/framework/adb.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/framework/utils.dart';
+
+/// Creates a device lab task that runs benchmarks in
+/// `dev/benchmarks/microbenchmarks` reports results to the dashboard.
+TaskFunction createMicrobenchmarkTask() {
+  return () async {
+    Device device = await devices.workingDevice;
+    await device.unlock();
+
+    Future<Map<String, double>> _runMicrobench(String benchmarkPath) async {
+      print('Running $benchmarkPath');
+      Directory appDir = dir(path.join(flutterDirectory.path, 'dev/benchmarks/microbenchmarks'));
+      Process flutterProcess = await inDirectory(appDir, () async {
+        return await _startFlutter(
+          options: <String>[
+            '--profile',  // --release doesn't work on iOS due to code signing issues
+            '-d',
+            device.deviceId,
+            benchmarkPath,
+          ],
+          canFail: false,
+        );
+      });
+
+      return await _readJsonResults(flutterProcess);
+    }
+
+    Map<String, double> allResults = <String, double>{};
+    allResults.addAll(await _runMicrobench('lib/stocks/layout_bench.dart'));
+    allResults.addAll(await _runMicrobench('lib/stocks/build_bench.dart'));
+    allResults.addAll(await _runMicrobench('lib/gestures/velocity_tracker_bench.dart'));
+    if (deviceOperatingSystem == DeviceOperatingSystem.android) {
+      // TODO(yjbanov): Run on iOS when https://github.com/flutter/flutter/issues/7433 is fixed.
+      allResults.addAll(await _runMicrobench('lib/stocks/animation_bench.dart'));
+    }
+
+    return new TaskResult.success(allResults, benchmarkScoreKeys: allResults.keys.toList());
+  };
+}
+
+Future<Process> _startFlutter({String command = 'run', List<String> options: const <String>[], bool canFail: false, Map<String, String> env}) {
+  List<String> args = <String>['run']..addAll(options);
+  return startProcess(path.join(flutterDirectory.path, 'bin', 'flutter'), args, env: env);
+}
+
+Future<Map<String, double>> _readJsonResults(Process process) {
+  // IMPORTANT: keep these values in sync with dev/benchmarks/microbenchmarks/lib/common.dart
+  const String jsonStart = '================ RESULTS ================';
+  const String jsonEnd = '================ FORMATTED ==============';
+  bool jsonStarted = false;
+  StringBuffer jsonBuf = new StringBuffer();
+  Completer<Map<String, double>> completer = new Completer<Map<String, double>>();
+  StreamSubscription<String> stdoutSub;
+
+  int prefixLength = 0;
+  stdoutSub = process.stdout
+      .transform(const Utf8Decoder())
+      .transform(const LineSplitter())
+      .listen((String line) {
+    print(line);
+
+    if (line.contains(jsonStart)) {
+      jsonStarted = true;
+      prefixLength = line.indexOf(jsonStart);
+      return;
+    }
+
+    if (line.contains(jsonEnd)) {
+      jsonStarted = false;
+      stdoutSub.cancel();
+      process.kill(ProcessSignal.SIGINT);  // flutter run doesn't quit automatically
+      completer.complete(JSON.decode(jsonBuf.toString()));
+      return;
+    }
+
+    if (jsonStarted)
+      jsonBuf.writeln(line.substring(prefixLength));
+  });
+
+  return completer.future;
+}