refactor(docs-infra): remove outdated comments regarding CustomEvent (#…

…44557)

remove the comments present in aio examples saying that for older
browsers such as IE CustomEvent could be necessary (as the the Event
constructor could be not available)

such comments are no longer necessary/relevant since the Event constructor
is available for all the supported browsers

PR Close #44557

aio/content/examples/testing/src/app/demo/demo.testbed.spec.ts

@@ -288,8 +288,6 @@ describe('demo (with TestBed):', () => {
 
         // Dispatch a DOM event so that Angular learns of input value change.
         // then wait while ngModel pushes input.box value to comp.name
-        // In older browsers, such as IE, you might need a CustomEvent instead. See
-        // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
         input.dispatchEvent(new Event('input'));
         return fixture.whenStable();
       })
@@ -332,8 +330,6 @@ describe('demo (with TestBed):', () => {
 
       // Dispatch a DOM event so that Angular learns of input value change.
       // then wait a tick while ngModel pushes input.box value to comp.name
-      // In older browsers, such as IE, you might need a CustomEvent instead. See
-      // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
       input.dispatchEvent(new Event('input'));
       tick();
       expect(comp.name)
@@ -358,8 +354,6 @@ describe('demo (with TestBed):', () => {
       // Dispatch a DOM event so that Angular learns of input value change.
       // then wait a tick while ngModel pushes input.box value to comp.text
       // and Angular updates the output span
-      // In older browsers, such as IE, you might need a CustomEvent instead. See
-      // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
       input.dispatchEvent(new Event('input'));
       tick();
       fixture.detectChanges();

aio/content/examples/testing/src/app/hero/hero-detail.component.spec.ts

@@ -102,8 +102,6 @@ function overrideSetup() {
 
        page.nameInput.value = newName;
 
-       // In older browsers, such as IE, you might need a CustomEvent instead. See
-       // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
        page.nameInput.dispatchEvent(new Event('input')); // tell Angular
 
        expect(component.hero.name)
@@ -223,8 +221,6 @@ function heroModuleSetup() {
       nameInput.value = 'quick BROWN  fOx';
 
       // Dispatch a DOM event so that Angular learns of input value change.
-      // In older browsers, such as IE, you might need a CustomEvent instead. See
-      // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
       nameInput.dispatchEvent(new Event('input'));
 
       // Tell Angular to update the display binding through the title pipe

aio/content/examples/testing/src/app/hero/hero-list.component.spec.ts

@@ -58,8 +58,6 @@ describe('HeroListComponent', () => {
        const expectedHero = HEROES[1];
        const btn = page.heroRows[1].querySelector('button');
 
-       // In older browsers, such as IE, you might need a CustomEvent instead. See
-       // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
        btn!.dispatchEvent(new Event('click'));
        tick();
        // `.toEqual` because selectedHero is clone of expectedHero; see FakeHeroService
@@ -70,8 +68,6 @@ describe('HeroListComponent', () => {
        const expectedHero = HEROES[1];
        const btn = page.heroRows[1].querySelector('button');
 
-       // In older browsers, such as IE, you might need a CustomEvent instead. See
-       // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
        btn!.dispatchEvent(new Event('click'));
        tick();
 

aio/content/examples/testing/src/app/shared/highlight.directive.spec.ts

@@ -63,8 +63,6 @@ describe('HighlightDirective', () => {
     input.value = 'green';
 
     // Dispatch a DOM event so that Angular responds to the input value change.
-    // In older browsers, such as IE, you might need a CustomEvent instead. See
-    // https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent/CustomEvent#Polyfill
     input.dispatchEvent(new Event('input'));
     fixture.detectChanges();