build: publish tree of files rather than FESMs (#18541)

* Remove now unnecessary portions of build.
* Add a compilePackageES5 method to build ES5 from sources
* Rework all package.json and rollup config files to new format
* Remove "extends" from tsconfig-build.json files and fixup compilation roots

PR Close #18541

tools/public_api_guard/platform-webworker/index.d.ts

@@ -0,0 +1,104 @@
+/** @experimental */
+export declare function bootstrapWorkerUi(workerScriptUri: string, customProviders?: StaticProvider[]): Promise<PlatformRef>;
+
+/** @experimental */
+export declare abstract class ClientMessageBroker {
+    abstract runOnService(args: UiArguments, returnType: Type<any> | SerializerTypes | null): Promise<any> | null;
+}
+
+/** @experimental */
+export declare abstract class ClientMessageBrokerFactory {
+    abstract createMessageBroker(channel: string, runInZone?: boolean): ClientMessageBroker;
+}
+
+/** @experimental */
+export declare class FnArg {
+    type: Type<any> | SerializerTypes;
+    value: any;
+    constructor(value: any, type?: Type<any> | SerializerTypes);
+}
+
+/** @experimental */
+export declare abstract class MessageBus implements MessageBusSource, MessageBusSink {
+    abstract attachToZone(zone: NgZone): void;
+    abstract from(channel: string): EventEmitter<any>;
+    abstract initChannel(channel: string, runInZone?: boolean): void;
+    abstract to(channel: string): EventEmitter<any>;
+}
+
+/** @experimental */
+export interface MessageBusSink {
+    attachToZone(zone: NgZone): void;
+    initChannel(channel: string, runInZone: boolean): void;
+    to(channel: string): EventEmitter<any>;
+}
+
+/** @experimental */
+export interface MessageBusSource {
+    attachToZone(zone: NgZone): void;
+    from(channel: string): EventEmitter<any>;
+    initChannel(channel: string, runInZone: boolean): void;
+}
+
+/** @experimental */
+export declare const platformWorkerApp: (extraProviders?: StaticProvider[] | undefined) => PlatformRef;
+
+/** @experimental */
+export declare const platformWorkerUi: (extraProviders?: StaticProvider[] | undefined) => PlatformRef;
+
+/** @experimental */
+export interface ReceivedMessage {
+    args: any[];
+    id: string;
+    method: string;
+    type: string;
+}
+
+/** @experimental */
+export declare const enum SerializerTypes {
+    RENDERER_TYPE_2 = 0,
+    PRIMITIVE = 1,
+    RENDER_STORE_OBJECT = 2,
+}
+
+/** @experimental */
+export declare abstract class ServiceMessageBroker {
+    abstract registerMethod(methodName: string, signature: Array<Type<any> | SerializerTypes> | null, method: Function, returnType?: Type<any> | SerializerTypes): void;
+}
+
+/** @experimental */
+export declare abstract class ServiceMessageBrokerFactory {
+    abstract createMessageBroker(channel: string, runInZone?: boolean): ServiceMessageBroker;
+}
+
+/** @experimental */
+export declare class UiArguments {
+    args: FnArg[];
+    method: string;
+    constructor(method: string, args?: FnArg[]);
+}
+
+/** @stable */
+export declare const VERSION: Version;
+
+/** @experimental */
+export declare const WORKER_APP_LOCATION_PROVIDERS: ({
+    provide: typeof PlatformLocation;
+    useClass: typeof WebWorkerPlatformLocation;
+} | {
+    provide: InjectionToken<(() => void)[]>;
+    useFactory: (platformLocation: WebWorkerPlatformLocation, zone: NgZone) => () => Promise<boolean>;
+    multi: boolean;
+    deps: (typeof NgZone | typeof PlatformLocation)[];
+} | {
+    provide: InjectionToken<Promise<any>>;
+    useFactory: (platformLocation: WebWorkerPlatformLocation) => Promise<any>;
+    deps: typeof PlatformLocation[];
+})[];
+
+/** @experimental */
+export declare const WORKER_UI_LOCATION_PROVIDERS: StaticProvider[];
+
+/** @experimental */
+export declare class WorkerAppModule {
+}