docs: testing guide for CLI (#20697)

- updates tests
- heavy prose revisions
- uses HttpClient (with angular-in-memory-web-api)
- test HeroService using `HttpClientTestingModule`
- scrub away most By.CSS
- fake async observable with `asyncData()`
- extensive Twain work
- different take on retryWhen
- remove app barrels (& systemjs.extras) which troubled plunker/systemjs
- add dummy export const to hero.ts (plunkr/systemjs fails w/o it)
- shrink and re-organize TOC
- add marble testing package and tests
- demonstrate the "no beforeEach()" test coding style
- add section on Http service testing
- prepare for stackblitz
- confirm works in plunker except excluded marble test
- add tests for avoidFile class feature of CodeExampleComponent

PR Close #20697

aio/tools/examples/shared/boilerplate/cli/package.json

@@ -35,6 +35,7 @@
     "@types/node": "~6.0.60",
     "codelyzer": "^4.0.1",
     "jasmine-core": "~2.8.0",
+    "jasmine-marbles": "~0.2.0",
     "jasmine-spec-reporter": "~4.2.1",
     "karma": "~2.0.0",
     "karma-chrome-launcher": "~2.2.0",

aio/tools/examples/shared/boilerplate/testing/package.json

@@ -1,51 +0,0 @@
-{
-  "name": "angular.io-example",
-  "version": "0.0.0",
-  "license": "MIT",
-  "scripts": {
-    "ng": "ng",
-    "start": "ng serve",
-    "build": "ng build",
-    "test": "ng test",
-    "lint": "ng lint",
-    "e2e": "ng e2e"
-  },
-  "private": true,
-  "dependencies": {
-    "@angular/animations": "^5.0.0",
-    "@angular/common": "^5.0.0",
-    "@angular/compiler": "^5.0.0",
-    "@angular/core": "^5.0.0",
-    "@angular/forms": "^5.0.0",
-    "@angular/http": "^5.0.0",
-    "@angular/platform-browser": "^5.0.0",
-    "@angular/platform-browser-dynamic": "^5.0.0",
-    "@angular/router": "^5.0.0",
-    "angular-in-memory-web-api": "~0.5.0",
-    "core-js": "^2.4.1",
-    "rxjs": "^5.5.2",
-    "zone.js": "^0.8.14"
-  },
-  "devDependencies": {
-    "@angular/cli": "1.5.4",
-    "@angular/compiler-cli": "^5.0.0",
-    "@angular/language-service": "^5.0.0",
-    "@types/jasmine": "~2.8.0",
-    "@types/jasminewd2": "~2.0.2",
-    "@types/node": "~6.0.60",
-    "codelyzer": "^4.0.1",
-    "jasmine-core": "~2.8.0",
-    "jasmine-marbles": "~2.8.0",
-    "jasmine-spec-reporter": "~4.1.0",
-    "karma": "~1.7.0",
-    "karma-chrome-launcher": "~2.1.1",
-    "karma-cli": "~1.0.1",
-    "karma-coverage-istanbul-reporter": "^1.2.1",
-    "karma-jasmine": "~1.1.0",
-    "karma-jasmine-html-reporter": "^0.2.2",
-    "protractor": "~5.1.2",
-    "ts-node": "~3.2.0",
-    "tslint": "~5.7.0",
-    "typescript": "~2.4.2"
-  }
-}

aio/tools/examples/shared/yarn.lock

@@ -3844,12 +3844,6 @@ jasmine-marbles@^0.2.0:
   dependencies:
     lodash "^4.5.0"
 
-jasmine-spec-reporter@^4.2.1:
-  version "4.2.1"
-  resolved "https://registry.yarnpkg.com/jasmine-spec-reporter/-/jasmine-spec-reporter-4.2.1.tgz#1d632aec0341670ad324f92ba84b4b32b35e9e22"
-  dependencies:
-    colors "1.1.2"
-
 jasmine@^2.5.3, jasmine@~2.8.0:
   version "2.8.0"
   resolved "https://registry.yarnpkg.com/jasmine/-/jasmine-2.8.0.tgz#6b089c0a11576b1f16df11b80146d91d4e8b8a3e"
@@ -3858,6 +3852,12 @@ jasmine@^2.5.3, jasmine@~2.8.0:
     glob "^7.0.6"
     jasmine-core "~2.8.0"
 
+jasmine-spec-reporter@^4.2.1:
+  version "4.2.1"
+  resolved "https://registry.yarnpkg.com/jasmine-spec-reporter/-/jasmine-spec-reporter-4.2.1.tgz#1d632aec0341670ad324f92ba84b4b32b35e9e22"
+  dependencies:
+    colors "1.1.2"
+
 jasminewd2@^2.1.0:
   version "2.2.0"
   resolved "https://registry.yarnpkg.com/jasminewd2/-/jasminewd2-2.2.0.tgz#e37cf0b17f199cce23bea71b2039395246b4ec4e"