Add Web Benchmarks for Flutter Gallery (Flutter Side) — 1/4 (#57576)

.cirrus.yml

@@ -18,8 +18,10 @@ web_shard_template: &WEB_SHARD_TEMPLATE
 linux_shard_template: &LINUX_SHARD_TEMPLATE
   environment:
     # Some of the host-only devicelab tests are pretty involved and need a lot of RAM.
-    CPU: 2
+    # In June 2020, the CPU and memory were increased so that
-    MEMORY: 8G
+    # web benchmarks (including gallery benchmarks) can be run successfully on Linux.
+    CPU: 4
+    MEMORY: 16G
   script:
     - dart --enable-asserts ./dev/bots/test.dart
 

dev/benchmarks/macrobenchmarks/lib/src/web/gallery/gallery_recorder.dart

@@ -0,0 +1,48 @@
+// 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/material.dart';
+
+import 'package:gallery/benchmarks/gallery_automator.dart';
+
+import 'package:macrobenchmarks/src/web/recorder.dart';
+
+/// A recorder that measures frame building durations for the Gallery.
+class GalleryRecorder extends WidgetRecorder {
+  GalleryRecorder({
+    @required this.benchmarkName,
+    this.shouldRunPredicate,
+    this.testScrollsOnly = false,
+  }) : assert(testScrollsOnly || shouldRunPredicate != null),
+       super(name: benchmarkName, useCustomWarmUp: true);
+
+  /// The name of the gallery benchmark to be run.
+  final String benchmarkName;
+
+  /// A function that accepts the name of a demo and returns whether we should
+  /// run this demo in this benchmark.
+  final bool Function(String) shouldRunPredicate;
+
+  /// Whether this benchmark only tests scrolling.
+  final bool testScrollsOnly;
+
+  /// Whether we should continue recording.
+  @override
+  bool shouldContinue() => !_finished || profile.shouldContinue();
+
+  GalleryAutomator _galleryAutomator;
+  bool get _finished => _galleryAutomator?.finished ?? false;
+
+  /// Creates the [GalleryAutomator] widget.
+  @override
+  Widget createWidget() {
+    _galleryAutomator = GalleryAutomator(
+      benchmarkName: benchmarkName,
+      shouldRunPredicate: shouldRunPredicate,
+      testScrollsOnly: testScrollsOnly,
+      stopWarmingUpCallback: profile.stopWarmingUp,
+    );
+    return _galleryAutomator.createWidget();
+  }
+}

dev/benchmarks/macrobenchmarks/lib/src/web/recorder.dart

@@ -235,7 +235,7 @@ abstract class SceneBuilderRecorder extends Recorder {
 
     window.onBeginFrame = (_) {
       try {
-        startMeasureFrame();
+        startMeasureFrame(profile);
         onBeginFrame();
       } catch (error, stackTrace) {
         profileCompleter.completeError(error, stackTrace);
@@ -333,7 +333,10 @@ abstract class SceneBuilderRecorder extends Recorder {
 /// }
 /// ```
 abstract class WidgetRecorder extends Recorder implements FrameRecorder {
-  WidgetRecorder({@required String name}) : super._(name, true);
+  WidgetRecorder({
+    @required String name,
+    this.useCustomWarmUp = false,
+  }) : super._(name, true);
 
   /// Creates a widget to be benchmarked.
   ///
@@ -349,12 +352,15 @@ abstract class WidgetRecorder extends Recorder implements FrameRecorder {
   Profile profile;
   Completer<void> _runCompleter;
 
+  /// Whether to delimit warm-up frames in a custom way.
+  final bool useCustomWarmUp;
+
   Stopwatch _drawFrameStopwatch;
 
   @override
   @mustCallSuper
   void frameWillDraw() {
-    startMeasureFrame();
+    startMeasureFrame(profile);
     _drawFrameStopwatch = Stopwatch()..start();
   }
 
@@ -380,7 +386,7 @@ abstract class WidgetRecorder extends Recorder implements FrameRecorder {
   @override
   Future<Profile> run() async {
     _runCompleter = Completer<void>();
-    final Profile localProfile = profile = Profile(name: name);
+    final Profile localProfile = profile = Profile(name: name, useCustomWarmUp: useCustomWarmUp);
     final _RecordingWidgetsBinding binding =
         _RecordingWidgetsBinding.ensureInitialized();
     final Widget widget = createWidget();
@@ -460,7 +466,7 @@ abstract class WidgetBuildRecorder extends Recorder implements FrameRecorder {
   @mustCallSuper
   void frameWillDraw() {
     if (showWidget) {
-      startMeasureFrame();
+      startMeasureFrame(profile);
       _drawFrameStopwatch = Stopwatch()..start();
     }
   }
@@ -538,7 +544,8 @@ class _WidgetBuildRecorderHostState extends State<_WidgetBuildRecorderHost> {
 /// calculations will only apply to the latest [_kMeasuredSampleCount] data
 /// points.
 class Timeseries {
-  Timeseries(this.name, this.isReported);
+  Timeseries(this.name, this.isReported, {this.useCustomWarmUp = false})
+      : _warmUpFrameCount = useCustomWarmUp ? 0 : null;
 
   /// The label of this timeseries used for debugging and result inspection.
   final String name;
@@ -553,6 +560,18 @@ class Timeseries {
   /// but that are too fine-grained to be useful for tracking on the dashboard.
   final bool isReported;
 
+  /// Whether to delimit warm-up frames in a custom way.
+  final bool useCustomWarmUp;
+
+  /// The number of frames ignored as warm-up frames, used only
+  /// when [useCustomWarmUp] is true.
+  int _warmUpFrameCount;
+
+  /// The number of frames ignored as warm-up frames.
+  int get warmUpFrameCount => useCustomWarmUp
+      ? _warmUpFrameCount
+      : count - _kMeasuredSampleCount;
+
   /// List of all the values that have been recorded.
   ///
   /// This list has no limit.
@@ -566,11 +585,15 @@ class Timeseries {
   ///
   /// See [TimeseriesStats] for more details.
   TimeseriesStats computeStats() {
+    final int finalWarmUpFrameCount = warmUpFrameCount;
+
+    assert(finalWarmUpFrameCount >= 0 && finalWarmUpFrameCount < count);
+
     // The first few values we simply discard and never look at. They're from the warm-up phase.
-    final List<double> warmUpValues = _allValues.sublist(0, _allValues.length - _kMeasuredSampleCount);
+    final List<double> warmUpValues = _allValues.sublist(0, finalWarmUpFrameCount);
 
     // Values we analyze.
-    final List<double> candidateValues = _allValues.sublist(_allValues.length - _kMeasuredSampleCount);
+    final List<double> candidateValues = _allValues.sublist(finalWarmUpFrameCount);
 
     // The average that includes outliers.
     final double dirtyAverage = _computeAverage(name, candidateValues);
@@ -628,13 +651,16 @@ class Timeseries {
   }
 
   /// Adds a value to this timeseries.
-  void add(double value) {
+  void add(double value, {@required bool isWarmUpValue}) {
     if (value < 0.0) {
       throw StateError(
         'Timeseries $name: negative metric values are not supported. Got: $value',
       );
     }
     _allValues.add(value);
+    if (useCustomWarmUp && isWarmUpValue) {
+      _warmUpFrameCount += 1;
+    }
   }
 }
 
@@ -748,11 +774,36 @@ class AnnotatedSample {
 
 /// Base class for a profile collected from running a benchmark.
 class Profile {
-  Profile({@required this.name}) : assert(name != null);
+  Profile({@required this.name, this.useCustomWarmUp = false})
+      : assert(name != null),
+        _isWarmingUp = useCustomWarmUp;
 
   /// The name of the benchmark that produced this profile.
   final String name;
 
+  /// Whether to delimit warm-up frames in a custom way.
+  final bool useCustomWarmUp;
+
+  /// Whether we are measuring warm-up frames currently.
+  bool get isWarmingUp => _isWarmingUp;
+
+  bool _isWarmingUp;
+
+  /// Stop the warm-up phase.
+  ///
+  /// Call this method only when [useCustomWarmUp] and [isWarmingUp] are both
+  /// true.
+  /// Call this method only once for each profile.
+  void stopWarmingUp() {
+    if (!useCustomWarmUp) {
+      throw Exception('`stopWarmingUp` should be used only when `useCustomWarmUp` is true.');
+    } else if (!_isWarmingUp) {
+      throw Exception('Warm-up already stopped.');
+    } else {
+      _isWarmingUp = false;
+    }
+  }
+
   /// This data will be used to display cards in the Flutter Dashboard.
   final Map<String, Timeseries> scoreData = <String, Timeseries>{};
 
@@ -773,7 +824,10 @@ class Profile {
   /// Set [reported] to `false` to store the data, but not show it on the
   /// dashboard UI.
   void addDataPoint(String key, Duration duration, { @required bool reported }) {
-    scoreData.putIfAbsent(key, () => Timeseries(key, reported)).add(duration.inMicroseconds.toDouble());
+    scoreData.putIfAbsent(
+        key,
+        () => Timeseries(key, reported, useCustomWarmUp: useCustomWarmUp),
+    ).add(duration.inMicroseconds.toDouble(), isWarmUpValue: isWarmingUp);
   }
 
   /// Decides whether the data collected so far is sufficient to stop, or
@@ -1007,6 +1061,20 @@ class _RecordingWidgetsBinding extends BindingBase
 
 int _currentFrameNumber = 1;
 
+/// If [_calledStartMeasureFrame] is true, we have called [startMeasureFrame]
+/// but have not its pairing [endMeasureFrame] yet.
+///
+/// This flag ensures that [startMeasureFrame] and [endMeasureFrame] are always
+/// called in pairs, with [startMeasureFrame] followed by [endMeasureFrame].
+bool _calledStartMeasureFrame = false;
+
+/// Whether we are recording a measured frame.
+///
+/// This flag ensures that we always stop measuring a frame if we
+/// have started one. Because we want to skip warm-up frames, this flag
+/// is necessary.
+bool _isMeasuringFrame = false;
+
 /// Adds a marker indication the beginning of frame rendering.
 ///
 /// This adds an event to the performance trace used to find measured frames in
@@ -1014,22 +1082,53 @@ int _currentFrameNumber = 1;
 /// benchmarks are only interested in a subset of frames. For example,
 /// [WidgetBuildRecorder] only measures frames that build widgets, and ignores
 /// frames that clear the screen.
-void startMeasureFrame() {
+///
-  html.window.performance.mark('measured_frame_start#$_currentFrameNumber');
+/// Warm-up frames are not measured. If [profile.isWarmingUp] is true,
+/// this function does nothing.
+void startMeasureFrame(Profile profile) {
+  if (_calledStartMeasureFrame) {
+    throw Exception('`startMeasureFrame` called twice in a row.');
+  }
+
+  _calledStartMeasureFrame = true;
+
+  if (!profile.isWarmingUp) {
+    // Tell the browser to mark the beginning of the frame.
+    html.window.performance.mark('measured_frame_start#$_currentFrameNumber');
+
+    _isMeasuringFrame = true;
+  }
 }
 
 /// Signals the end of a measured frame.
 ///
 /// See [startMeasureFrame] for details on what this instrumentation is used
 /// for.
+///
+/// Warm-up frames are not measured. If [profile.isWarmingUp] was true
+/// when the corresponding [startMeasureFrame] was called,
+/// this function does nothing.
 void endMeasureFrame() {
-  html.window.performance.mark('measured_frame_end#$_currentFrameNumber');
+  if (!_calledStartMeasureFrame) {
-  html.window.performance.measure(
+    throw Exception('`startMeasureFrame` has not been called before calling `endMeasureFrame`');
-    'measured_frame',
+  }
-    'measured_frame_start#$_currentFrameNumber',
+
-    'measured_frame_end#$_currentFrameNumber',
+  _calledStartMeasureFrame = false;
-  );
+
-  _currentFrameNumber += 1;
+  if (_isMeasuringFrame) {
+    // Tell the browser to mark the end of the frame, and measure the duration.
+    html.window.performance.mark('measured_frame_end#$_currentFrameNumber');
+    html.window.performance.measure(
+      'measured_frame',
+      'measured_frame_start#$_currentFrameNumber',
+      'measured_frame_end#$_currentFrameNumber',
+    );
+
+    // Increment the current frame number.
+    _currentFrameNumber += 1;
+
+    _isMeasuringFrame = false;
+  }
 }
 
 /// A function that receives a benchmark value from the framework.

dev/benchmarks/macrobenchmarks/lib/web_benchmarks.dart

@@ -10,6 +10,8 @@ import 'dart:math' as math;
 import 'package:macrobenchmarks/src/web/bench_text_layout.dart';
 import 'package:macrobenchmarks/src/web/bench_text_out_of_picture_bounds.dart';
 
+import 'package:gallery/benchmarks/gallery_automator.dart' show DemoType, typeOfDemo;
+
 import 'src/web/bench_build_material_checkbox.dart';
 import 'src/web/bench_card_infinite_scroll.dart';
 import 'src/web/bench_child_layers.dart';
@@ -22,12 +24,15 @@ import 'src/web/bench_paths.dart';
 import 'src/web/bench_picture_recording.dart';
 import 'src/web/bench_simple_lazy_text_scroll.dart';
 import 'src/web/bench_text_out_of_picture_bounds.dart';
+import 'src/web/gallery/gallery_recorder.dart';
 import 'src/web/recorder.dart';
 
 typedef RecorderFactory = Recorder Function();
 
 const bool isCanvasKit = bool.fromEnvironment('FLUTTER_WEB_USE_SKIA', defaultValue: false);
 
+const String _galleryBenchmarkPrefix = 'gallery_v2';
+
 /// List of all benchmarks that run in the devicelab.
 ///
 /// When adding a new benchmark, add it to this map. Make sure that the name
@@ -57,7 +62,16 @@ final Map<String, RecorderFactory> benchmarks = <String, RecorderFactory>{
     BenchTextCachedLayout.canvasBenchmarkName: () => BenchTextCachedLayout(useCanvas: true),
     BenchBuildColorsGrid.domBenchmarkName: () => BenchBuildColorsGrid.dom(),
     BenchBuildColorsGrid.canvasBenchmarkName: () => BenchBuildColorsGrid.canvas(),
-  }
+
+    // The following benchmark is for the Flutter Gallery.
+    // This benchmark is failing when run with CanvasKit, so we skip it
+    // for now.
+    // TODO(yjbanov): https://github.com/flutter/flutter/issues/59082
+    '${_galleryBenchmarkPrefix}_studies_perf': () => GalleryRecorder(
+      benchmarkName: '${_galleryBenchmarkPrefix}_studies_perf',
+      shouldRunPredicate: (String demo) => typeOfDemo(demo) == DemoType.study,
+    ),
+  },
 };
 
 final LocalBenchmarkServerClient _client = LocalBenchmarkServerClient();
@@ -83,29 +97,48 @@ Future<void> _runBenchmark(String benchmarkName) async {
     return;
   }
 
-  try {
+  await runZoned<Future<void>>(
-    final Recorder recorder = recorderFactory();
+    () async {
-    final Runner runner = recorder.isTracingEnabled && !_client.isInManualMode
+      final Recorder recorder = recorderFactory();
-      ? Runner(
+      final Runner runner = recorder.isTracingEnabled && !_client.isInManualMode
-          recorder: recorder,
+          ? Runner(
-          setUpAllDidRun: () => _client.startPerformanceTracing(benchmarkName),
+              recorder: recorder,
-          tearDownAllWillRun: _client.stopPerformanceTracing,
+              setUpAllDidRun: () => _client.startPerformanceTracing(benchmarkName),
-        )
+              tearDownAllWillRun: _client.stopPerformanceTracing,
-      : Runner(recorder: recorder);
+            )
+          : Runner(recorder: recorder);
 
-    final Profile profile = await runner.run();
+      final Profile profile = await runner.run();
-    if (!_client.isInManualMode) {
+      if (!_client.isInManualMode) {
-      await _client.sendProfileData(profile);
+        await _client.sendProfileData(profile);
-    } else {
+      } else {
-      _printResultsToScreen(profile);
+        _printResultsToScreen(profile);
-      print(profile);
+        print(profile);
-    }
+      }
-  } catch (error, stackTrace) {
+    },
-    if (_client.isInManualMode) {
+    zoneSpecification: ZoneSpecification(
-      rethrow;
+      print: (Zone self, ZoneDelegate parent, Zone zone, String line) async {
-    }
+        if (_client.isInManualMode) {
-    await _client.reportError(error, stackTrace);
+          parent.print(zone, '[$benchmarkName] $line');
-  }
+        } else {
+          await _client.printToConsole(line);
+        }
+      },
+      handleUncaughtError: (
+        Zone self,
+        ZoneDelegate parent,
+        Zone zone, Object error,
+        StackTrace stackTrace,
+      ) async {
+        if (_client.isInManualMode) {
+          parent.print(zone, '[$benchmarkName] $error, $stackTrace');
+          parent.handleUncaughtError(zone, error, stackTrace);
+        } else {
+          await _client.reportError(error, stackTrace);
+        }
+      },
+    ),
+  );
 }
 
 void _fallbackToManual(String error) {
@@ -354,6 +387,17 @@ class LocalBenchmarkServerClient {
     );
   }
 
+  /// Reports a message about the demo to the benchmark server.
+  Future<void> printToConsole(String report) async {
+    _checkNotManualMode();
+    await html.HttpRequest.request(
+      '/print-to-console',
+      method: 'POST',
+      mimeType: 'text/plain',
+      sendData: report,
+    );
+  }
+
   /// This is the same as calling [html.HttpRequest.request] but it doesn't
   /// crash on 404, which we use to detect `flutter run`.
   Future<html.HttpRequest> _requestXhr(

dev/benchmarks/macrobenchmarks/pubspec.yaml

@@ -17,6 +17,12 @@ dependencies:
   #   flutter update-packages --force-upgrade
   flutter_gallery_assets: 0.2.1
 
+  # This is needed for web_benchmarks.
+  gallery:
+    git:
+      url: https://github.com/flutter/gallery.git
+      ref: 0c5ec2f285c1ec30b2ed15194bc8de755654a590
+
   archive: 2.0.13 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   args: 1.6.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   async: 2.4.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
@@ -87,8 +93,173 @@ dev_dependencies:
 flutter:
   uses-material-design: true
   assets:
-  - packages/flutter_gallery_assets/food/butternut_squash_soup.png
+    - packages/flutter_gallery_assets/food/butternut_squash_soup.png
-  - packages/flutter_gallery_assets/food/cherry_pie.png
+    - packages/flutter_gallery_assets/food/cherry_pie.png
-  - assets/999x1000.png
+    - assets/999x1000.png
+
+    # The following assets are required for running Flutter Gallery benchmarks.
+    - packages/flutter_gallery_assets/assets/icons/settings/settings_light.flr
+    - packages/flutter_gallery_assets/assets/icons/settings/settings_dark.flr
+    - packages/flutter_gallery_assets/assets/studies/shrine_card_dark.png
+    - packages/flutter_gallery_assets/assets/studies/starter_card.png
+    - packages/flutter_gallery_assets/assets/studies/starter_card_dark.png
+    - packages/flutter_gallery_assets/assets/studies/fortnightly_card_dark.png
+    - packages/flutter_gallery_assets/assets/studies/rally_card_dark.png
+    - packages/flutter_gallery_assets/assets/studies/fortnightly_card.png
+    - packages/flutter_gallery_assets/assets/studies/crane_card.png
+    - packages/flutter_gallery_assets/assets/studies/shrine_card.png
+    - packages/flutter_gallery_assets/assets/studies/crane_card_dark.png
+    - packages/flutter_gallery_assets/assets/studies/rally_card.png
+    - packages/flutter_gallery_assets/assets/logo/flutter_logo.png
+    - packages/flutter_gallery_assets/assets/logo/flutter_logo_color.png
+    - packages/flutter_gallery_assets/assets/icons/cupertino/cupertino.png
+    - packages/flutter_gallery_assets/assets/icons/material/material.png
+    - packages/flutter_gallery_assets/assets/icons/reference/reference.png
+    - packages/flutter_gallery_assets/assets/demos/bottom_navigation_background.png
+    - packages/flutter_gallery_assets/fonts/GalleryIcons.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Merriweather-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Eczar-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Montserrat-Medium.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Rubik-Bold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Merriweather-Light.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/RobotoCondensed-Bold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Raleway-Medium.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Raleway-SemiBold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/LibreFranklin-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/RobotoMono-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/LibreFranklin-ExtraBold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/LibreFranklin-Bold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Oswald-SemiBold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Oswald-Medium.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/LibreFranklin-SemiBold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Raleway-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Montserrat-Bold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Merriweather-BoldItalic.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Raleway-Light.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Rubik-Medium.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Montserrat-SemiBold.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/RobotoCondensed-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/LibreFranklin-Medium.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Montserrat-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Rubik-Regular.ttf
+    - packages/flutter_gallery_assets/fonts/google_fonts/Eczar-SemiBold.ttf
+    - packages/flutter_gallery_assets/crane/destinations/eat_1.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_2.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_3.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_4.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_5.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_6.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_7.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_8.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_9.jpg
+    - packages/flutter_gallery_assets/crane/destinations/eat_10.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_0.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_1.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_2.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_3.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_4.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_5.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_6.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_7.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_8.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_9.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_10.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_11.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_12.jpg
+    - packages/flutter_gallery_assets/crane/destinations/fly_13.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_0.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_1.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_2.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_3.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_4.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_5.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_6.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_7.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_8.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_9.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_10.jpg
+    - packages/flutter_gallery_assets/crane/destinations/sleep_11.jpg
+    - packages/flutter_gallery_assets/crane/logo/logo.png
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_army.png
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_bees.jpg
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_chart.png
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_fabrics.png
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_feminists.jpg
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_gas.png
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_healthcare.jpg
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_stocks.png
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_title.png
+    - packages/flutter_gallery_assets/fortnightly/fortnightly_war.png
+    - packages/flutter_gallery_assets/places/india_chennai_flower_market.png
+    - packages/flutter_gallery_assets/places/india_thanjavur_market.png
+    - packages/flutter_gallery_assets/places/india_tanjore_bronze_works.png
+    - packages/flutter_gallery_assets/places/india_tanjore_market_merchant.png
+    - packages/flutter_gallery_assets/places/india_tanjore_thanjavur_temple.png
+    - packages/flutter_gallery_assets/places/india_pondicherry_salt_farm.png
+    - packages/flutter_gallery_assets/places/india_chennai_highway.png
+    - packages/flutter_gallery_assets/places/india_chettinad_silk_maker.png
+    - packages/flutter_gallery_assets/places/india_tanjore_thanjavur_temple_carvings.png
+    - packages/flutter_gallery_assets/places/india_chettinad_produce.png
+    - packages/flutter_gallery_assets/places/india_tanjore_market_technology.png
+    - packages/flutter_gallery_assets/places/india_pondicherry_beach.png
+    - packages/flutter_gallery_assets/places/india_pondicherry_fisherman.png
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_1.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_2.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_3.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_4.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_5.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_6.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_7.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_8.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_9.gif
+    - packages/flutter_gallery_assets/splash_effects/splash_effect_10.gif
+    - packages/rally_assets/logo.png
+    - packages/rally_assets/thumb.png
+    - packages/shrine_images/diamond.png
+    - packages/shrine_images/slanted_menu.png
+    - packages/shrine_images/0-0.jpg
+    - packages/shrine_images/1-0.jpg
+    - packages/shrine_images/2-0.jpg
+    - packages/shrine_images/3-0.jpg
+    - packages/shrine_images/4-0.jpg
+    - packages/shrine_images/5-0.jpg
+    - packages/shrine_images/6-0.jpg
+    - packages/shrine_images/7-0.jpg
+    - packages/shrine_images/8-0.jpg
+    - packages/shrine_images/9-0.jpg
+    - packages/shrine_images/10-0.jpg
+    - packages/shrine_images/11-0.jpg
+    - packages/shrine_images/12-0.jpg
+    - packages/shrine_images/13-0.jpg
+    - packages/shrine_images/14-0.jpg
+    - packages/shrine_images/15-0.jpg
+    - packages/shrine_images/16-0.jpg
+    - packages/shrine_images/17-0.jpg
+    - packages/shrine_images/18-0.jpg
+    - packages/shrine_images/19-0.jpg
+    - packages/shrine_images/20-0.jpg
+    - packages/shrine_images/21-0.jpg
+    - packages/shrine_images/22-0.jpg
+    - packages/shrine_images/23-0.jpg
+    - packages/shrine_images/24-0.jpg
+    - packages/shrine_images/25-0.jpg
+    - packages/shrine_images/26-0.jpg
+    - packages/shrine_images/27-0.jpg
+    - packages/shrine_images/28-0.jpg
+    - packages/shrine_images/29-0.jpg
+    - packages/shrine_images/30-0.jpg
+    - packages/shrine_images/31-0.jpg
+    - packages/shrine_images/32-0.jpg
+    - packages/shrine_images/33-0.jpg
+    - packages/shrine_images/34-0.jpg
+    - packages/shrine_images/35-0.jpg
+    - packages/shrine_images/36-0.jpg
+    - packages/shrine_images/37-0.jpg
+
+  # The following font is required for running Flutter Gallery benchmarks.
+  fonts:
+    - family: GalleryIcons
+      fonts:
+        - asset: packages/flutter_gallery_assets/fonts/GalleryIcons.ttf
 
 # PUBSPEC CHECKSUM: 8ced

dev/devicelab/lib/tasks/web_benchmarks.dart

@@ -99,6 +99,13 @@ Future<TaskResult> runWebBenchmark({ @required bool useCanvasKit }) async {
             profileData.complete(collectedProfiles);
             return Response.notFound('Finished running benchmarks.');
           }
+        } else if (request.requestedUri.path.endsWith('/print-to-console')) {
+          // A passthrough used by
+          // `dev/benchmarks/macrobenchmarks/lib/web_benchmarks.dart`
+          // to print information.
+          final String message = await request.readAsString();
+          print('[Gallery] $message');
+          return Response.ok('Reported.');
         } else {
           return Response.notFound(
               'This request is not handled by the profile-data handler.');