Adds StandardMessageCodec benchmark (#101767)

dev/benchmarks/microbenchmarks/lib/foundation/standard_message_codec_bench.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 'package:flutter/services.dart';
+
+import '../common.dart';
+
+const int _kNumIterations = 100000;
+
+void main() {
+  assert(false,
+      "Don't run benchmarks in checked mode! Use 'flutter run --release'.");
+  final BenchmarkResultPrinter printer = BenchmarkResultPrinter();
+
+  const StandardMessageCodec codec = StandardMessageCodec();
+  final Stopwatch watch = Stopwatch();
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMessage(null);
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMessageCodec null',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMessageCodec_null',
+  );
+
+  watch.reset();
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMessage(12345);
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMessageCodec int',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMessageCodec_int',
+  );
+
+  watch.reset();
+
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMessage('This is a performance test.');
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMessageCodec string',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMessageCodec_string',
+  );
+
+  watch.reset();
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMessage(<Object>[1234, 'This is a performance test.', 1.25, true]);
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMessageCodec heterogenous list',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMessageCodec_heterogenous_list',
+  );
+
+  watch.reset();
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMessage(<String, Object>{
+      'integer': 1234,
+      'string': 'This is a performance test.',
+      'float': 1.25,
+      'boolean': true
+    });
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMessageCodec heterogenous map',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMessageCodec_heterogenous_map',
+  );
+
+  watch.reset();
+
+  printer.printToStdout();
+}

dev/devicelab/lib/tasks/microbenchmarks.dart

@@ -61,6 +61,7 @@ TaskFunction createMicrobenchmarkTask() {
       ...await _runMicrobench('lib/language/sync_star_semantics_bench.dart'),
       ...await _runMicrobench('lib/foundation/all_elements_bench.dart'),
       ...await _runMicrobench('lib/foundation/change_notifier_bench.dart'),
+      ...await _runMicrobench('lib/foundation/standard_message_codec_bench.dart'),
       ...await _runMicrobench('lib/foundation/timeline_bench.dart'),
     };