PersistentClient reconnect should subscribe to 'inner client' 'close' event

[raintonr]

It seems that sometimes a Chromecast device will disconnect from a client connected with this module.

There is a section of code in PersistentClient that looks like it is designed to cater for such events here:

https://github.com/angelnu/castv2-player/blob/523fd5a8317656a5038b7a7b3ca9d1de4e89f1a7/lib/persistentClient.js#L252

Ie. looks like PersistentClient is supposed to catch any close events and reconnect.

However, the 'client' in this case is not actually a direct 'client' but the a sender class (PlatformSender), which does not actually emit 'close' events and therefore PersistentClient fails to reconnect as I assume it is designed to do.

This manifests itself as issues such as iobroker-community-adapters/ioBroker.chromecast#36

As noted there, a fix is discussed here: thibauts/node-castv2-client#58 (comment), and indeed changing the line referenced above to use the 'inner client' works for me. Ie. change...

            //If connection closes afterwards then re-open it again
            that._client.once("close", function(){
              that._close();
              that._connectClient();
            });

...should be changed to...

            //If connection closes afterwards then re-open it again
            that._client.client.once("close", function(){
              that._close();
              that._connectClient();
            });