Prevent Sync / WebUI from closing when launched from Production Configuration page and reload is triggered in background due to timer

[isc-tleavitt]

Right now this is very jarring and a pain in the neck.

There's a related upstream issue (internal ref: DP-424937) but I think git-source-control could do some clever things around this with either (a) a lock on the CSP session (which is a blunt instrument and possibly problematic) or (b) communication back to the parent frame.

[isc-tleavitt]

Possible simple approach to (b): attempt to get the old value of window.parent.zenPage.enableAutoRefresh; if successful and true, set to false and set back to true in onbeforeunload eventhandler.