chore: remove obsolete dart related files

modules/benchmarks_external/src/tree/react/index.dart

@@ -1 +0,0 @@
-library benchmarks_external.src.tree.react;

modules/benchmarks_external/src/tree/tree_benchmark.dart

@@ -1,73 +0,0 @@
-// tree benchmark in AngularDart 1.x
-library tree_benchmark_ng10;
-
-import 'package:angular/angular.dart';
-import 'package:angular/application_factory.dart';
-import 'package:angular2/src/testing/benchmark_util.dart';
-
-setup() {
-  var m = new Module()
-    ..bind(CompilerConfig,
-        toValue: new CompilerConfig.withOptions(elementProbeEnabled: false))
-    ..bind(ScopeDigestTTL,
-        toFactory: () => new ScopeDigestTTL.value(15), inject: [])
-    ..bind(TreeComponent);
-
-  final injector = applicationFactory().addModule(m).run();
-
-  return injector;
-}
-
-main() {
-  var maxDepth = getIntParameter('depth');
-
-  final injector = setup();
-  final zone = injector.get(VmTurnZone);
-  final rootScope = injector.get(Scope);
-  var count = 0;
-
-  destroyDom() {
-    zone.run(() {
-      rootScope.context['initData'] = new TreeNode('');
-    });
-  }
-
-  createDom() {
-    zone.run(() {
-      var values = count++ % 2 == 0
-          ? ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '*']
-          : ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', '-'];
-
-      rootScope.context['initData'] = buildTree(maxDepth, values, 0);
-    });
-  }
-
-  bindAction('#destroyDom', destroyDom);
-  bindAction('#createDom', createDom);
-}
-
-@Component(
-    selector: 'tree',
-    map: const {'data': '=>data'},
-    template: '<span> {{data.value}}'
-        '<span ng-if="data.right != null"><tree data=data.right></span>'
-        '<span ng-if="data.left != null"><tree data=data.left></span>'
-        '</span>')
-class TreeComponent {
-  var data;
-}
-
-buildTree(maxDepth, values, curDepth) {
-  if (maxDepth == curDepth) return new TreeNode('');
-  return new TreeNode(
-      values[curDepth],
-      buildTree(maxDepth, values, curDepth + 1),
-      buildTree(maxDepth, values, curDepth + 1));
-}
-
-class TreeNode {
-  var value;
-  TreeNode left;
-  TreeNode right;
-  TreeNode([this.value, this.left, this.right]);
-}