Advanced settings JSON input error

[lukasolson]

1. Go to advanced settings
2. For any of the JSON inputs, try emptying out the input then saving

You won't see an error in the UI. It will look like it's trying to save. If you look at the developer console, you'll see the following:

angular.js:12477 SyntaxError: Unexpected end of JSON input
    at JSON.parse (<anonymous>)
    at getCurrentValue (config.js:175)
    at Object.config.get (config.js:33)
    at advertise (config.js:151)
    at localUpdate (config.js:130)
    at change (config.js:118)
    at Object.config.set (config.js:36)
    at advanced_row.js:60
    at loading (advanced_row.js:36)
    at Scope.$scope.save (advanced_row.js:55)

I'd expect either of the following instead:

1. The save button is disabled until you enter valid JSON (this is what happens when you type something that isn't valid JSON into the input), or
2. The save is successful and just saves with an empty JSON object.