Prevent execution of sendBeacon() / sendShutdown() in JavaScript part of RAP

[eclipse-rap]

Prevent execution of sendBeacon() / sendShutdown() in JavaScript part of RAP

[mknauer]

As a background: In RAP 3.21 we added the ability to handle and to intercept HTTP redirects with commit d4d5c38.

After some consideration, we believe that the suppression of the shutdown request belongs to the entry point, i.e. it should be possible to configure it differently for each entry point, as opposed to configuring it at the application level.

An example configuration in the ApplicationConfiguration could look as follows and include a new WebClient constant DISABLE_SHUTDOWN_REQUEST. This is just an additional property that is used during the initialisation of the entry point:

Map<String, String> properties = new HashMap<String, String>();
properties.put( WebClient.DISABLE_SHUTDOWN_REQUEST, "true" );
application.addEntryPoint( "/", Demo.class, properties );