Better error handling for broken JSON - Cannot read property 'channel' of undefined

Non-valid JSON can lead the nodejs server to fail while trying to create logging output:

C:\xampp\htdocs\drupal\sites\all\modules\nodejs\server.js:319
Error calling getContentTokenChannelUsers() for channel "' + channel.channel +
                                                                    ^
TypeError: Cannot read property 'channel' of undefined
    at IncomingMessage.<anonymous> (C:\xampp\htdocs\drupal\sites\all\modules\nod
ejs\server.js:319:98)
    at IncomingMessage.EventEmitter.emit (events.js:92:17)
    at _stream_readable.js:895:16
    at process._tickCallback (node.js:415:13)

Patch attached: Ignore non-compliant JSON better