build: move zone.js to angular repo (#30962)

PR Close #30962

packages/zone.js/example/benchmarks/event_emitter.js

@@ -0,0 +1,50 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+const events = require('events');
+const EventEmitter = events.EventEmitter;
+require('../../dist/zone-node');
+
+const emitters = [];
+const callbacks = [];
+const size = 100000;
+for (let i = 0; i < size; i++) {
+  const emitter = new EventEmitter();
+  const callback = (function(i) { return function() { console.log(i); }; })(i);
+  emitters[i] = emitter;
+  callbacks[i] = callback;
+}
+
+function addRemoveCallback(reuse, useZone) {
+  const start = new Date();
+  let callback = callbacks[0];
+  for (let i = 0; i < size; i++) {
+    const emitter = emitters[i];
+    if (!reuse) callback = callbacks[i];
+    if (useZone)
+      emitter.on('msg', callback);
+    else
+      emitter.__zone_symbol__addListener('msg', callback);
+  }
+
+  for (let i = 0; i < size; i++) {
+    const emitter = emitters[i];
+    if (!reuse) callback = callbacks[i];
+    if (useZone)
+      emitter.removeListener('msg', callback);
+    else
+      emitter.__zone_symbol__removeListener('msg', callback);
+  }
+  const end = new Date();
+  console.log(useZone ? 'use zone' : 'native', reuse ? 'reuse' : 'new');
+  console.log('Execution time: %dms', end - start);
+}
+
+addRemoveCallback(false, false);
+addRemoveCallback(false, true);
+addRemoveCallback(true, false);
+addRemoveCallback(true, true);