build(bazel): Turning on strictPropertyInitialization for Angular. (#24572)

All errors for existing fields have been detected and suppressed with a
`!` assertion.

Issue/24571 is tracking proper clean up of those instances.

One-line change required in ivy/compilation.ts, because it appears that
the new syntax causes tsickle emitted node to no longer track their
original sourceFiles.

PR Close #24572

packages/elements/test/create-custom-element_spec.ts

@@ -103,7 +103,8 @@ if (typeof customElements !== 'undefined') {
 })
 class TestComponent {
   @Input() fooFoo: string = 'foo';
-  @Input('barbar') barBar: string;
+  // TODO(issue/24571): remove '!'.
+  @Input('barbar') barBar !: string;
 
   @Output() bazBaz = new EventEmitter<boolean>();
   @Output('quxqux') quxQux = new EventEmitter<Object>();