[MIE-1185] Fix issues when favoriting on IE9/10

XMLHttpRequest fails whenever withCredentials=true is called before .open() (Refer to http://www.w3.org/TR/2012/WD-XMLHttpRequest-20120117/#the-withcredentials-attribute).

Fix this by moving the line after the .open() call, the same way the DELETE method is implemented

JIRA: https://jira.nationalgeographic.com/browse/MIE-1185