wrappedCallback = function(value) {
      try {
        return (isFunction(callback) ? callback : defaultCallback)(value);
      } catch (e) {
        exceptionHandler(e);
        return reject(e);
      }
    }
@ngdoc method
@name $q#when
@kind function

@description
Wraps an object that might be a value or a (3rd party) then-able promise into a $q promise.
This is useful when you are dealing with an object that might or might not be a promise, or if
the promise comes from a source that can't be trusted.

@param {*} value Value or a promise
@returns {Promise} Returns a promise of the passed value or promise