Hi,

When I subscribe the warcher to the NULL object property (e.g. keypath is 'Object.prop', where prop == null). The exception occures when I call unsubscriber.

Sample code:

var unwatch = vm.$watch('keypath', function (newVal, oldVal) {
});

unwatch(); // here the exception fires

The cause of the exception is a following code (exports._destroy function):

      for (i in this._userWatchers) {
        this._userWatchers[i].teardown()
      }