fix(ivy): error when using forwardRef in Injectable's useClass (#30532)

Fixes Ivy throwing an error when something is passed in as a `forwardRef` into `@Injectable`'s `useClass` option. The error was being thrown, because we were trying to get the provider factory off of the wrapper function, rather than the value itself.

This PR resolves FW-1335.

PR Close #30532

packages/core/src/di/forward_ref.ts

@@ -57,11 +57,11 @@ export function forwardRef(forwardRefFn: ForwardRefFn): Type<any> {
  * @publicApi
  */
 export function resolveForwardRef<T>(type: T): T {
-  const fn: any = type;
-  if (typeof fn === 'function' && fn.hasOwnProperty(__forward_ref__) &&
-      fn.__forward_ref__ === forwardRef) {
-    return fn();
-  } else {
-    return type;
-  }
+  return isForwardRef(type) ? type() : type;
+}
+
+/** Checks whether a function is wrapped by a `forwardRef`. */
+export function isForwardRef(fn: any): fn is() => any {
+  return typeof fn === 'function' && fn.hasOwnProperty(__forward_ref__) &&
+      fn.__forward_ref__ === forwardRef;
 }

packages/core/src/di/jit/environment.ts

@@ -7,6 +7,7 @@
  */
 
 import {Type} from '../../interface/type';
+import {isForwardRef, resolveForwardRef} from '../forward_ref';
 import {ɵɵinject} from '../injector_compatibility';
 import {getInjectableDef, getInjectorDef, ɵɵdefineInjectable, ɵɵdefineInjector} from '../interface/defs';
 
@@ -26,6 +27,14 @@ export const angularCoreDiEnv: {[name: string]: Function} = {
 
 function getFactoryOf<T>(type: Type<any>): ((type?: Type<T>) => T)|null {
   const typeAny = type as any;
+
+  if (isForwardRef(type)) {
+    return (() => {
+      const factory = getFactoryOf<T>(resolveForwardRef(typeAny));
+      return factory ? factory() : null;
+    }) as any;
+  }
+
   const def = getInjectableDef<T>(typeAny) || getInjectorDef<T>(typeAny);
   if (!def || def.factory === undefined) {
     return null;