fix(InternalStore): invalid value on parse

if you get an invalid value JSON.parse throws an error

localcache = {
  'yolo': undefined // should be "{swag: true, isAuthenticated: true}"
};

store.get('yolo') // JSON.parse error is thrown


localcache
inside a <code>catch</code> javascript doesn't hoist variables but I mistook that rule also applying to context which it doesn't so I'll remove <code>self</code>