Revert "refactor(core): add ApplicationRef.prototype.bootstrapImpl with an injector parameter (angular#60622)" (angular#60669)

This reverts commit 7cb8639.

PR Close angular#60669

Author: thePunderWoman

packages/core/src/application/application_ref.ts

@@ -498,14 +498,6 @@ export class ApplicationRef {
   bootstrap<C>(
     componentOrFactory: ComponentFactory<C> | Type<C>,
     rootSelectorOrNode?: string | any,
-  ): ComponentRef<C> {
-    return this.bootstrapImpl(componentOrFactory, rootSelectorOrNode);
-  }
-
-  private bootstrapImpl<C>(
-    componentOrFactory: ComponentFactory<C> | Type<C>,
-    rootSelectorOrNode?: string | any,
-    injector: Injector = Injector.NULL,
   ): ComponentRef<C> {
     profiler(ProfilerEvent.BootstrapComponentStart);
 
@@ -540,7 +532,7 @@ export class ApplicationRef {
       ? undefined
       : this._injector.get(NgModuleRef);
     const selectorOrNode = rootSelectorOrNode || componentFactory.selector;
-    const compRef = componentFactory.create(injector, [], selectorOrNode, ngModule);
+    const compRef = componentFactory.create(Injector.NULL, [], selectorOrNode, ngModule);
     const nativeElement = compRef.location.nativeElement;
     const testability = compRef.injector.get(TESTABILITY, null);
     testability?.registerApplication(nativeElement);

packages/core/test/application_ref_spec.ts

@@ -254,34 +254,6 @@ describe('bootstrap', () => {
         ),
       );
     });
-
-    describe('bootstrapImpl', () => {
-      it('should use a provided injector', inject([ApplicationRef], (ref: ApplicationRef) => {
-        class MyService {}
-        const myService = new MyService();
-
-        @Component({
-          selector: 'injecting-component',
-          template: `<div>Hello, World!</div>`,
-        })
-        class InjectingComponent {
-          constructor(readonly myService: MyService) {}
-        }
-
-        const injector = Injector.create({
-          providers: [{provide: MyService, useValue: myService}],
-        });
-
-        createRootEl('injecting-component');
-        const appRef = ref as unknown as {bootstrapImpl: ApplicationRef['bootstrapImpl']};
-        const compRef = appRef.bootstrapImpl(
-          InjectingComponent,
-          /* rootSelectorOrNode */ undefined,
-          injector,
-        );
-        expect(compRef.instance.myService).toBe(myService);
-      }));
-    });
   });
 
   describe('destroy', () => {