Revert: "feat(router): add navigationSource and restoredState to NavigationStart event (#21728)"

This reverts commit 3b7bab7d22. Will be re-merged after fixing integration of minor breaking change.

packages/platform-server/src/location.ts

@@ -63,9 +63,8 @@ export class ServerPlatformLocation implements PlatformLocation {
     }
     (this as{hash: string}).hash = value;
     const newUrl = this.url;
-    scheduleMicroTask(() => this._hashUpdate.next({
-      type: 'hashchange', state: null, oldUrl, newUrl
-    } as LocationChangeEvent));
+    scheduleMicroTask(
+        () => this._hashUpdate.next({ type: 'hashchange', oldUrl, newUrl } as LocationChangeEvent));
   }
 
   replaceState(state: any, title: string, newUrl: string): void {