System.err: java.net.ConnectException: Connection timed out not handled by angular NS

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Modules involved: import { HttpClient, HttpHeaders, HttpResponse, HttpErrorResponse } from "@angular/common/http";
TNS info:

✔ Getting NativeScript components versions information...
⚠ Update available for component nativescript. Your current version is 4.0.0 and the latest available version is 4.0.1.
✔ Component tns-core-modules has 4.0.0 version and is up to date.
✔ Component tns-android has 4.0.1 version and is up to date.
✔ Component tns-ios has 4.0.1 version and is up to date.

node version: v9.8.0
tns --version : 4.0.0

Case:
Using a simple POST request and not passing timeout parameter will return a Unknown Error, no status code no HttpErrorResponse object.

Nativescript Angular: handles the timeout using import "rxjs/add/operator/timeout"; but this just deattach the subscriber from the Observable and returns nothing, and then after java has consume the http request time android returns a System.err: java.net.ConnectException: Connection timed out but Nativescript angular is not able to determine the object type so if no timeout parameter is added from angular, angular returns a Unknown Error response which is not ok because from angular we should be able to set up timeout options that affects in fact the android / java stack so that way when android fails we can get the HttpErrorResponse object.

How to replicate:

this.http.post(url, body, { headers: headers })
            .timeout(3000).catch(this.handleTimeout)
            .map(response =>{
                return response;
            })
            .catch(this.handleErrors);
handleTimeout(error) {
        console.log(error);
        return error;
    }

In the console we got: JS: TimeoutError: Timeout has occurred which is not an HttpResponseError object.
After the error is returned wait 5 more minutes and check the console for this:

JS: TimeoutError: Timeout has occurred
System.err: java.net.ConnectException: Connection timed out
System.err:     at java.net.PlainSocketImpl.socketConnect(Native Method)
System.err:     at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:343)
System.err:     at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:205)
System.err:     at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:187)
System.err:     at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:356)
System.err:     at java.net.Socket.connect(Socket.java:586)
System.err:     at com.android.okhttp.internal.Platform.connectSocket(Platform.java:113)
System.err:     at com.android.okhttp.Connection.connectSocket(Connection.java:196)
System.err:     at com.android.okhttp.Connection.connect(Connection.java:172)
System.err:     at com.android.okhttp.Connection.connectAndSetOwner(Connection.java:367)
System.err:     at com.android.okhttp.OkHttpClient$1.connectAndSetOwner(OkHttpClient.java:130)
System.err:     at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:329)
System.err:     at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:246)
System.err:     at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:457)
System.err:     at com.android.okhttp.internal.huc.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:126)
System.err:     at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getOutputStream(HttpURLConnectionImpl.java:257)
System.err:     at com.android.okhttp.internal.huc.DelegatingHttpsURLConnection.getOutputStream(DelegatingHttpsURLConnection.java:218)
System.err:     at com.android.okhttp.internal.huc.HttpsURLConnectionImpl.getOutputStream(HttpsURLConnectionImpl.java)
System.err:     at org.nativescript.widgets.Async$Http$RequestOptions.writeContent(Async.java:313)
System.err:     at org.nativescript.widgets.Async$Http$HttpRequestTask.doInBackground(Async.java:536)
System.err:     at org.nativescript.widgets.Async$Http$1.run(Async.java:482)
System.err:     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
System.err:     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
System.err:     at org.nativescript.widgets.Async$PriorityThreadFactory$1.run(Async.java:52)
System.err:     at java.lang.Thread.run(Thread.java:761)

If no timeout handler is added angular should get the HttpResponseError object but is not, it is just returning "Unknown error".