Sharepoint Check In Rest API Error 'Not well formatted JSON stream'

Question

The same Check In Rest API working in Sharepoint provider hosted low trust app but in High trust app it gives Error 'Not well formatted JSON stream'

    <!-- language: lang-js -->
    var spUrl = appweburl + "/_api/SP.AppContextSite(@target)/web/getfilebyserverrelativeurl('" + fnGetServerRelPath(sFileRef) + "')/checkin(comment='Check-In',checkintype=0)?@target='" + hostweburl + "'";
     var executor = new SP.RequestExecutor(appweburl);
     executor.executeAsync({
                            url: spUrl,
                            method: "POST",
                            headers: { "Accept": "application/json; odata=verbose" },
                            binaryStringResponseBody: false,
                            success: function (data) { },
                            error: function (data) { fnUpdateFileFailure(data) },
                            state: "Update"
                });

Answer 1

I Just change the header and it works for me !

headers: {
          "X-HTTP-Method": "PUT", 
           "accept": "application/json; odata=verbose" 
         },