Discussing CB-5806 [Windows8] Add keepCallback support to proxy

[Sergey Grebnov (Akvelon)]

Hi,
I've just found out that due to current windows8 proxy implementation[1] 
plugins can't specify keepCalback parameter since result of proxy function is 
always treated as resultant message only. On other platforms we have options to 
also specify callbackId, custom callbackStatus and keepCallback parameters.

I believe correct implementation way is treating callback result as plugin 
result object which should include callbackId, status, keepCallback, message, 
etc ...but we can't change this behavior right now since it will break all 
already implemented plugins. So I propose the following two solutions:

1. add keepCallback as second optional parameter

            onSuccess = function (result, keepCallback) {
                cordova.callbackSuccess(callbackId,
                        {
                        status: cordova.callbackStatus.OK,
                        message: result,
                        keepCallback: keepCallback == true
                    });

  Usage:  onSuccess(res, true);  onSuccess(undefined, true);

 2. allow plugins to specify keepCallback as part of result
 
  onSuccess = function (result) {
                cordova.callbackSuccess(callbackId,
                        {
                        status: cordova.callbackStatus.OK,
                        message: result,
                        keepCallback: result && result.keepCallback == true
                    });

I personally prefer #1, Thoughts?

[1] https://github.com/apache/cordova-js/blob/master/src/windows8/exec.js#L57

PS. There is aame problem with callbackId

Thx!
Sergey