fix(core): export provider interfaces that are part of the public API types (#31377)

Some of the provider interfaces that the [Provider][1] and
[StaticProvider][2] types comprise were not exported from
[@angular/core][3]. As a result, the docs for these symbols did not
appear on angular.io (even though both `Provider` and `StaticProvider`
are part of the public API. (See, also,
https://github.com/angular/angular/pull/31377#discussion_r299254408.)

This commit fixes it by exporting all necessary provider interfaces.

[1]: https://github.com/angular/angular/blob/9e34670b2/packages/core/src/di/interface/provider.ts#L365-L366
[2]: https://github.com/angular/angular/blob/9e34670b2/packages/core/src/di/interface/provider.ts#L283-L284
[3]: https://github.com/angular/angular/blob/9e34670b2/packages/core/src/di/index.ts#L23

PR Close #31377

packages/core/src/di/index.ts

@@ -20,7 +20,7 @@ export {Injectable, InjectableDecorator, InjectableProvider} from './injectable'
 export {Injector} from './injector';
 export {ɵɵinject, inject, INJECTOR} from './injector_compatibility';
 export {ReflectiveInjector} from './reflective_injector';
-export {StaticProvider, ValueProvider, ConstructorSansProvider, ExistingProvider, FactoryProvider, Provider, TypeProvider, ClassProvider, ValueSansProvider, ClassSansProvider} from './interface/provider';
+export {ClassProvider, ClassSansProvider, ConstructorProvider, ConstructorSansProvider, ExistingProvider, ExistingSansProvider, FactoryProvider, FactorySansProvider, Provider, StaticClassProvider, StaticClassSansProvider, StaticProvider, TypeProvider, ValueProvider, ValueSansProvider} from './interface/provider';
 export {ResolvedReflectiveFactory, ResolvedReflectiveProvider} from './reflective_provider';
 export {ReflectiveKey} from './reflective_key';
 export {InjectionToken} from './injection_token';

packages/core/src/di/interface/provider.ts

@@ -164,12 +164,6 @@ export interface ConstructorProvider extends ConstructorSansProvider {
  *
  * For more details, see the ["Dependency Injection Guide"](guide/dependency-injection).
  *
- * @usageNotes
- *
- * ### Example
- *
- * {@example core/di/ts/provider_spec.ts region='ExistingSansProvider'}
- *
  * @publicApi
  */
 export interface ExistingSansProvider {
@@ -214,11 +208,6 @@ export interface ExistingProvider extends ExistingSansProvider {
  *
  * For more details, see the ["Dependency Injection Guide"](guide/dependency-injection).
  *
- * @usageNotes
- * ### Example
- *
- * {@example core/di/ts/provider_spec.ts region='FactorySansProvider'}
- *
  * @publicApi
  */
 export interface FactorySansProvider {

tools/public_api_guard/core/core.d.ts

@@ -165,6 +165,11 @@ export declare abstract class ComponentRef<C> {
     abstract onDestroy(callback: Function): void;
 }
 
+export interface ConstructorProvider extends ConstructorSansProvider {
+    multi?: boolean;
+    provide: Type<any>;
+}
+
 export interface ConstructorSansProvider {
     deps?: any[];
 }
@@ -332,11 +337,20 @@ export interface ExistingProvider extends ExistingSansProvider {
     provide: any;
 }
 
+export interface ExistingSansProvider {
+    useExisting: any;
+}
+
 export interface FactoryProvider extends FactorySansProvider {
     multi?: boolean;
     provide: any;
 }
 
+export interface FactorySansProvider {
+    deps?: any[];
+    useFactory: Function;
+}
+
 export declare function forwardRef(forwardRefFn: ForwardRefFn): Type<any>;
 
 export interface ForwardRefFn {
@@ -1345,6 +1359,16 @@ export interface SkipSelfDecorator {
     new (): SkipSelf;
 }
 
+export interface StaticClassProvider extends StaticClassSansProvider {
+    multi?: boolean;
+    provide: any;
+}
+
+export interface StaticClassSansProvider {
+    deps: any[];
+    useClass: Type<any>;
+}
+
 export declare type StaticProvider = ValueProvider | ExistingProvider | StaticClassProvider | ConstructorProvider | FactoryProvider | any[];
 
 /** @deprecated */