Add some basic benchmarks of the Stocks app

 - animation_bench.dart. This benchmark measures the full main-thread pipeline
   for ticking the drawer entrance and exit animation.
 - build_bench.dart. This benchmark measures a full app rebuild when there's no
   state change.
 - layout_bench.dart. This benchmark measures a full relayout.

packages/flutter_sprites/.gitignore

-.DS_Store
-.idea
-.packages
-.pub/
-build/
-packages
-pubspec.lock

packages/flx/.gitignore

-.idea
-.pub/
-pubspec.lock

packages/unit/.gitignore

-.pub
-packages
-pubspec.lock

packages/unit/benchmark/stocks/animation_bench.dart

+import 'dart:io';
+
+import 'package:flutter/rendering.dart';
+import 'package:flutter/material.dart';
+import 'package:stocks/main.dart' as stocks;
+import 'package:stocks/stock_data.dart' as stock_data;
+import '../../test/widget/widget_tester.dart';
+
+const int _kNumberOfIterations = 50000;
+const bool _kRunForever = true;
+
+void main() {
+  assert(false); // Don't run in checked mode
+  stock_data.StockDataFetcher.actuallyFetchData = false;
+
+  const Duration _kAnimationDuration = const Duration(milliseconds: 200);
+  const Duration tickDuration = const Duration(milliseconds: 2);
+  int numberOfTicks = _kAnimationDuration.inMicroseconds ~/ tickDuration.inMicroseconds;
+  int numberOfRounts = _kNumberOfIterations ~/ numberOfTicks;
+
+  Stopwatch watch = new Stopwatch()
+    ..start();
+
+  testWidgets((WidgetTester tester) {
+    stocks.main();
+    tester.pump(); // Start startup animation
+    tester.pump(const Duration(seconds: 1)); // Complete startup animation
+
+    bool drawerIsOpen = false;
+
+    for (int i = 0; i < numberOfRounts || _kRunForever; ++i) {
+      if (drawerIsOpen)
+        tester.tapAt(const Point(20.0, 20.0)); // Open drawer
+      else
+        tester.tapAt(const Point(780.0, 20.0)); // Close drawer
+
+      tester.pump(); // Start drawer animation
+
+      for (int j = 0; j < numberOfTicks; ++j)
+        tester.pump(tickDuration);
+
+      tester.pump(const Duration(seconds: 1)); // Complete animation
+      drawerIsOpen = !drawerIsOpen;
+    }
+  });
+
+  watch.stop();
+  print("Stock animation: " + watch.elapsed.toString());
+
+  exit(0);
+}

packages/unit/benchmark/stocks/build_bench.dart

+import 'dart:io';
+
+import 'package:flutter/rendering.dart';
+import 'package:flutter/material.dart';
+import 'package:stocks/main.dart' as stocks;
+import 'package:stocks/stock_data.dart' as stock_data;
+import '../../test/widget/widget_tester.dart';
+
+const int _kNumberOfIterations = 100000;
+const bool _kRunForever = true;
+
+void _doNothing() { }
+
+void main() {
+  assert(false); // Don't run in checked mode
+  stock_data.StockDataFetcher.actuallyFetchData = false;
+
+  stocks.StocksAppState appState;
+
+  testWidgets((WidgetTester tester) {
+    stocks.main();
+    tester.pump(); // Start startup animation
+    tester.pump(const Duration(seconds: 1)); // Complete startup animation
+    tester.tapAt(new Point(20.0, 20.0)); // Open drawer
+    tester.pump(); // Start drawer animation
+    tester.pump(const Duration(seconds: 1)); // Complete drawer animation
+    appState = tester.findStateOfType(stocks.StocksAppState);
+  });
+
+  WidgetFlutterBinding binding = WidgetFlutterBinding.instance;
+
+  Stopwatch watch = new Stopwatch()
+    ..start();
+
+  for (int i = 0; i < _kNumberOfIterations || _kRunForever; ++i) {
+    appState.setState(_doNothing);
+    binding.buildDirtyElements();
+  }
+
+  watch.stop();
+  print("Stock build: " + watch.elapsed.toString());
+  exit(0);
+}

packages/unit/benchmark/stocks/layout_bench.dart

+import 'dart:io';
+
+import 'package:flutter/rendering.dart';
+import 'package:flutter/material.dart';
+import 'package:stocks/main.dart' as stocks;
+import 'package:stocks/stock_data.dart' as stock_data;
+import '../../test/widget/widget_tester.dart';
+
+const int _kNumberOfIterations = 100000;
+const bool _kRunForever = false;
+
+void main() {
+  assert(false); // Don't run in checked mode
+  stock_data.StockDataFetcher.actuallyFetchData = false;
+
+  testWidgets((WidgetTester tester) {
+    stocks.main();
+    tester.pump(); // Start startup animation
+    tester.pump(const Duration(seconds: 1)); // Complete startup animation
+    tester.tapAt(new Point(20.0, 20.0)); // Open drawer
+    tester.pump(); // Start drawer animation
+    tester.pump(const Duration(seconds: 1)); // Complete drawer animation
+  });
+
+  ViewConstraints big = const ViewConstraints(size: const Size(360.0, 640.0));
+  ViewConstraints small = const ViewConstraints(size: const Size(355.0, 635.0));
+  RenderView renderView = WidgetFlutterBinding.instance.renderView;
+
+  Stopwatch watch = new Stopwatch()
+    ..start();
+
+  for (int i = 0; i < _kNumberOfIterations || _kRunForever; ++i) {
+    renderView.rootConstraints = (i % 2 == 0) ? big : small;
+    RenderObject.flushLayout();
+  }
+
+  watch.stop();
+  print("Stock layout: " + watch.elapsed.toString());
+  exit(0);
+}

packages/unit/pubspec.yaml

@@ -6,5 +6,7 @@ dependencies:
     path: ../flx
   flutter:
     path: ../flutter
+  stocks:
+    path: ../../examples/stocks
   sky_tools:
     path: ../flutter_tools