feat(benchmarks): Add basic dart transformer benchmarks.

Adds simple benchmarks for various transformation phases, as well as hello_world.
Does not integrate these into any benchmark frameworks yet.

modules/angular2/test/benchmark/transform/directive_processor/simple.dart

@@ -0,0 +1,35 @@
+library angular2.benchmark.transform.directive_processor.simple;
+
+import 'dart:async';
+import 'package:angular2/src/transform/common/options.dart';
+import 'package:angular2/src/transform/directive_processor/transformer.dart';
+import 'package:barback/barback.dart';
+import 'package:code_transformers/benchmarks.dart';
+import 'package:unittest/unittest.dart';
+
+Future main() => runBenchmark();
+
+allTests() {
+  test('Directive Processor Benchmark Runs', runBenchmark);
+}
+
+Future runBenchmark() async {
+  var options = new TransformerOptions(['this_is_ignored.dart']);
+  var files = {new AssetId('a', 'a.dart'): aContents,};
+  var benchmark =
+      new TransformerBenchmark([[new DirectiveProcessor(options)]], files);
+  print('\nRunning directive_processor benchmark...');
+  var result = await benchmark.measure();
+  print('Done, took ${result.round()}μs on average.');
+}
+
+const aContents = '''
+library dinner.soup;
+
+import 'package:angular2/src/core/annotations/annotations.dart';
+
+@Component(selector: '[soup]')
+class SoupComponent {
+  SoupComponent(@Tasty String description, @Inject(Salt) salt);
+}
+''';