//Chamado por um botão
start()
{
    this.geolocation.getCurrentPosition(opts).then((resp: any) => {
        console.log("latitude:", resp.coords.latitude);
        console.log("longitude:", resp.coords.longitude);
    }).catch((err: any) => {
        console.log('ERRO:', err.message);
        console.log('Code:', err.code);
    });
}

latitude: -0000000000
longitude: -0000000000

ERRO: Only secure origins are allowed (see: ...)
code: 1

ionic plugin rm cordova-plugin-geolocation

ionic plugin rm cordova-plugin-geolocation@latest --save

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
 <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
 <uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />