fix(upgrade): ensure downgraded components are destroyed in the Angular zone

packages/upgrade/src/common/downgrade_component_adapter.ts

@@ -203,11 +203,13 @@ export class DowngradeComponentAdapter {
   }
 
   registerCleanup(needsNgZone: boolean) {
+    const destroyComponentRef = this.wrapCallback(() => this.componentRef.destroy());
+
     this.element.on !('$destroy', () => {
       this.componentScope.$destroy();
       this.componentRef.injector.get(TestabilityRegistry)
           .unregisterApplication(this.componentRef.location.nativeElement);
-      this.componentRef.destroy();
+      destroyComponentRef();
       if (needsNgZone) {
         this.appRef.detachView(this.componentRef.hostView);
       }

packages/upgrade/test/common/downgrade_component_adapter_spec.ts

@@ -122,7 +122,7 @@ export function main() {
         let $compile = undefined as any;
         let $parse = undefined as any;
         let componentFactory: ComponentFactory<any>;  // testbed
-        let wrapCallback = undefined as any;
+        let wrapCallback = (cb: any) => cb;
 
         content = `
           <h1> new component </h1>
@@ -183,7 +183,7 @@ export function main() {
         expect(registry.getAllTestabilities().length).toEqual(0);
         adapter.createComponent([]);
         expect(registry.getAllTestabilities().length).toEqual(1);
-        adapter.registerCleanup(true);
+        adapter.registerCleanup();
         element.remove !();
         expect(registry.getAllTestabilities().length).toEqual(0);
       });

packages/upgrade/test/static/integration/downgrade_module_spec.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {Component, Inject, Injector, Input, NgModule, NgZone, OnChanges, StaticProvider, destroyPlatform} from '@angular/core';
+import {Component, Inject, Injector, Input, NgModule, NgZone, OnChanges, OnDestroy, StaticProvider, destroyPlatform} from '@angular/core';
 import {async, fakeAsync, tick} from '@angular/core/testing';
 import {BrowserModule} from '@angular/platform-browser';
 import {platformBrowserDynamic} from '@angular/platform-browser-dynamic';
@@ -170,6 +170,42 @@ export function main() {
            });
          }));
 
+      it('should destroy components inside the Angular zone', async(() => {
+           let destroyedInTheZone = false;
+
+           @Component({selector: 'ng2', template: ''})
+           class Ng2Component implements OnDestroy {
+             ngOnDestroy() { destroyedInTheZone = NgZone.isInAngularZone(); }
+           }
+
+           @NgModule({
+             declarations: [Ng2Component],
+             entryComponents: [Ng2Component],
+             imports: [BrowserModule],
+           })
+           class Ng2Module {
+             ngDoBootstrap() {}
+           }
+
+           const bootstrapFn = (extraProviders: StaticProvider[]) =>
+               platformBrowserDynamic(extraProviders).bootstrapModule(Ng2Module);
+           const lazyModuleName = downgradeModule<Ng2Module>(bootstrapFn);
+           const ng1Module =
+               angular.module('ng1', [lazyModuleName])
+                   .directive(
+                       'ng2', downgradeComponent({component: Ng2Component, propagateDigest}));
+
+           const element = html('<ng2 ng-if="!hideNg2"></ng2>');
+           const $injector = angular.bootstrap(element, [ng1Module.name]);
+           const $rootScope = $injector.get($ROOT_SCOPE) as angular.IRootScopeService;
+
+           // Wait for the module to be bootstrapped.
+           setTimeout(() => {
+             $rootScope.$apply('hideNg2 = true');
+             expect(destroyedInTheZone).toBe(true);
+           });
+         }));
+
       it('should propagate input changes inside the Angular zone', async(() => {
            let ng2Component: Ng2Component;