feat(core): upgrade rxjs to 6.0.0-alpha.4 (#22573)

PR Close #22573

aio/content/examples/reactive-forms/src/app/demo.component.ts

@@ -1,6 +1,7 @@
 /* tslint:disable:member-ordering */
 import { Component }  from '@angular/core';
-import { Observable } from 'rxjs/Observable';
+import { Observable } from 'rxjs';
+import { finalize } from 'rxjs/operators';
 
 import { Hero }        from './data-model';
 import { HeroService } from './hero.service';
@@ -33,8 +34,9 @@ export class DemoComponent {
 
   getHeroes() {
     this.isLoading = true;
-    this.heroes = this.heroService.getHeroes()
-                      .finally(() => this.isLoading = false);
+    this.heroes = this.heroService.getHeroes().pipe(
+                      finalize(() => this.isLoading = false)
+    );
     this.selectedHero = undefined;
   }
 

aio/content/examples/reactive-forms/src/app/hero-list/hero-list.component.ts

@@ -1,7 +1,7 @@
 // #docregion
 import { Component, OnInit } from '@angular/core';
-import { Observable }        from 'rxjs/Observable';
-import 'rxjs/add/operator/finally';
+import { Observable }        from 'rxjs';
+import { finalize } from 'rxjs/operators';
 
 import { Hero }        from '../data-model';
 import { HeroService } from '../hero.service';
@@ -24,7 +24,7 @@ export class HeroListComponent implements OnInit {
     this.isLoading = true;
     this.heroes = this.heroService.getHeroes()
                       // Todo: error handling
-                      .finally(() => this.isLoading = false);
+                      .pipe(finalize(() => this.isLoading = false));
     this.selectedHero = undefined;
   }
 

aio/content/examples/reactive-forms/src/app/hero.service.ts

@@ -1,9 +1,8 @@
 // #docregion
 import { Injectable } from '@angular/core';
 
-import { Observable } from 'rxjs/Observable';
-import { of }         from 'rxjs/observable/of';
-import 'rxjs/add/operator/delay';
+import { Observable, of } from 'rxjs';
+import { delay } from 'rxjs/operators';
 
 import { Hero, heroes } from './data-model';
 
@@ -14,13 +13,13 @@ export class HeroService {
 
   // Fake server get; assume nothing can go wrong
   getHeroes(): Observable<Hero[]> {
-    return of(heroes).delay(this.delayMs); // simulate latency with delay
+    return of(heroes).pipe(delay(this.delayMs)); // simulate latency with delay
   }
 
   // Fake server update; assume nothing can go wrong
   updateHero(hero: Hero): Observable<Hero>  {
     const oldHero = heroes.find(h => h.id === hero.id);
     const newHero = Object.assign(oldHero, hero); // Demo: mutate cached hero
-    return of(newHero).delay(this.delayMs); // simulate latency with delay
+    return of(newHero).pipe(delay(this.delayMs)); // simulate latency with delay
   }
 }