refactor: remove EventEmitter from facade (#14837)

As of right now each module has its own copy of the EventEmitter
contributing to bloat.

modules/@angular/core/src/core.ts

@@ -29,7 +29,7 @@ export {TRANSLATIONS, TRANSLATIONS_FORMAT, LOCALE_ID, MissingTranslationStrategy
 export {ApplicationModule} from './application_module';
 export {wtfCreateScope, wtfLeave, wtfStartTimeRange, wtfEndTimeRange, WtfScopeFn} from './profile/profile';
 export {Type} from './type';
-export {EventEmitter} from './facade/async';
+export {EventEmitter} from './event_emitter';
 export {ErrorHandler} from './error_handler';
 export * from './core_private_export';
 export {Sanitizer, SecurityContext} from './security';
@@ -59,4 +59,4 @@ export type AnimationStyles = any;
 /**
  * @deprecated from v4
  */
-export type AnimationKeyframe = any;
+export type AnimationKeyframe = any;

modules/@angular/core/src/event_emitter.ts

@@ -0,0 +1,113 @@
+/**
+ * @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
+ */
+
+import {Subject} from 'rxjs/Subject';
+
+/**
+ * Use by directives and components to emit custom Events.
+ *
+ * ### Examples
+ *
+ * In the following example, `Zippy` alternatively emits `open` and `close` events when its
+ * title gets clicked:
+ *
+ * ```
+ * @Component({
+ *   selector: 'zippy',
+ *   template: `
+ *   <div class="zippy">
+ *     <div (click)="toggle()">Toggle</div>
+ *     <div [hidden]="!visible">
+ *       <ng-content></ng-content>
+ *     </div>
+ *  </div>`})
+ * export class Zippy {
+ *   visible: boolean = true;
+ *   @Output() open: EventEmitter<any> = new EventEmitter();
+ *   @Output() close: EventEmitter<any> = new EventEmitter();
+ *
+ *   toggle() {
+ *     this.visible = !this.visible;
+ *     if (this.visible) {
+ *       this.open.emit(null);
+ *     } else {
+ *       this.close.emit(null);
+ *     }
+ *   }
+ * }
+ * ```
+ *
+ * The events payload can be accessed by the parameter `$event` on the components output event
+ * handler:
+ *
+ * ```
+ * <zippy (open)="onOpen($event)" (close)="onClose($event)"></zippy>
+ * ```
+ *
+ * Uses Rx.Observable but provides an adapter to make it work as specified here:
+ * https://github.com/jhusain/observable-spec
+ *
+ * Once a reference implementation of the spec is available, switch to it.
+ * @stable
+ */
+export class EventEmitter<T> extends Subject<T> {
+  // TODO: mark this as internal once all the facades are gone
+  // we can't mark it as internal now because EventEmitter exported via @angular/core would not
+  // contain this property making it incompatible with all the code that uses EventEmitter via
+  // facades, which are local to the code and do not have this property stripped.
+  // tslint:disable-next-line
+  __isAsync: boolean;
+
+  /**
+   * Creates an instance of [EventEmitter], which depending on [isAsync],
+   * delivers events synchronously or asynchronously.
+   */
+  constructor(isAsync: boolean = false) {
+    super();
+    this.__isAsync = isAsync;
+  }
+
+  emit(value?: T) { super.next(value); }
+
+  subscribe(generatorOrNext?: any, error?: any, complete?: any): any {
+    let schedulerFn: (t: any) => any;
+    let errorFn = (err: any): any => null;
+    let completeFn = (): any => null;
+
+    if (generatorOrNext && typeof generatorOrNext === 'object') {
+      schedulerFn = this.__isAsync ? (value: any) => {
+        setTimeout(() => generatorOrNext.next(value));
+      } : (value: any) => { generatorOrNext.next(value); };
+
+      if (generatorOrNext.error) {
+        errorFn = this.__isAsync ? (err) => { setTimeout(() => generatorOrNext.error(err)); } :
+                                   (err) => { generatorOrNext.error(err); };
+      }
+
+      if (generatorOrNext.complete) {
+        completeFn = this.__isAsync ? () => { setTimeout(() => generatorOrNext.complete()); } :
+                                      () => { generatorOrNext.complete(); };
+      }
+    } else {
+      schedulerFn = this.__isAsync ? (value: any) => { setTimeout(() => generatorOrNext(value)); } :
+                                     (value: any) => { generatorOrNext(value); };
+
+      if (error) {
+        errorFn =
+            this.__isAsync ? (err) => { setTimeout(() => error(err)); } : (err) => { error(err); };
+      }
+
+      if (complete) {
+        completeFn =
+            this.__isAsync ? () => { setTimeout(() => complete()); } : () => { complete(); };
+      }
+    }
+
+    return super.subscribe(schedulerFn, errorFn, completeFn);
+  }
+}

modules/@angular/core/src/linker/query_list.ts

@@ -6,10 +6,13 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {EventEmitter, Observable} from '../facade/async';
+import {Observable} from 'rxjs/Observable';
+
+import {EventEmitter} from '../event_emitter';
 import {ListWrapper} from '../facade/collection';
 import {getSymbolIterator} from '../facade/lang';
 
+
 /**
  * An unmodifiable list of items that Angular keeps up to date when the state
  * of the application changes.

modules/@angular/core/src/zone/ng_zone.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {EventEmitter} from '../facade/async';
+import {EventEmitter} from '../event_emitter';
 
 /**
  * An injectable service for executing work inside or outside of the Angular zone.