fix(language-service): Turn on strict mode for test project (#32783)

This is the last part in refactoring of the test project.
This PR turns on strict mode for typechecking and fixed tests that
fail under this mode.

PR Close #32783

packages/language-service/test/project/app/app.component.ts

@@ -8,7 +8,7 @@
 
 import {Component} from '@angular/core';
 
-export class Hero {
+export interface Hero {
   id: number;
   name: string;
 }
@@ -30,5 +30,5 @@ export class Hero {
 export class AppComponent {
   title = 'Tour of Heroes';
   hero: Hero = {id: 1, name: 'Windstorm'};
-  private internal: string;
+  private internal: string = 'internal';
 }

packages/language-service/test/project/app/expression-cases.ts

@@ -44,5 +44,5 @@ export class ExpectNumericType {
   template: '{{ (name | lowercase).~{string-pipe}substring }}',
 })
 export class LowercasePipe {
-  name: string;
+  name: string = 'name';
 }

packages/language-service/test/project/app/ng-for-cases.ts

@@ -29,7 +29,7 @@ export class UnknownPeople {
     </div>`,
 })
 export class UnknownEven {
-  people: Person[];
+  people: Person[] = [];
 }
 
 @Component({
@@ -39,5 +39,5 @@ export class UnknownEven {
     </div>`,
 })
 export class UnknownTrackBy {
-  people: Person[];
+  people: Person[] = [];
 }

packages/language-service/test/project/app/parsing-cases.ts

@@ -49,21 +49,21 @@ export class NoValueAttribute {
   template: '<h1 model="~{attribute-binding-model}test"></h1>',
 })
 export class AttributeBinding {
-  test: string;
+  test: string = 'test';
 }
 
 @Component({
   template: '<h1 [model]="~{property-binding-model}test"></h1>',
 })
 export class PropertyBinding {
-  test: string;
+  test: string = 'test';
 }
 
 @Component({
   template: '<h1 (model)="~{event-binding-model}modelChanged()"></h1>',
 })
 export class EventBinding {
-  test: string;
+  test: string = 'test';
 
   modelChanged() {}
 }
@@ -72,23 +72,23 @@ export class EventBinding {
   template: '<h1 [(model)]="~{two-way-binding-model}test"></h1>',
 })
 export class TwoWayBinding {
-  test: string;
+  test: string = 'test';
 }
 
 @Directive({
   selector: '[string-model]',
 })
 export class StringModel {
-  @Input() model: string;
-  @Output() modelChanged: EventEmitter<string>;
+  @Input() model: string = 'model';
+  @Output() modelChanged: EventEmitter<string> = new EventEmitter();
 }
 
 @Directive({
   selector: '[number-model]',
 })
 export class NumberModel {
-  @Input('inputAlias') model: number;
-  @Output('outputAlias') modelChanged: EventEmitter<number>;
+  @Input('inputAlias') model: number = 0;
+  @Output('outputAlias') modelChanged: EventEmitter<number> = new EventEmitter();
 }
 
 interface Person {
@@ -122,7 +122,7 @@ export class ForLetIEqual {
     </div>`,
 })
 export class ForUsingComponent {
-  people: Person[];
+  people: Person[] = [];
 }
 
 @Component({