Error in Edit_Js, If you hide the contact_id field in Inventory records

The JS code which copies address data from related records into Inventory records when a user clicks the "Related" Radio button causes a Fatal error if you have hidden the Contact Name, UIType 10 field. This example is from a Quote.

Fatal error: Uncaught Exception: Bad Request in /var/www/html/dev/vtlib/Vtiger/Functions.php:1512 
Stack trace: #0 /var/www/html/dev/includes/http/Request.php(22): Vtiger_Functions::validateRequestParameters(Array) 
             #1 /var/www/html/dev/index.php(20): Vtiger_Request->__construct(Array, Array) 
             #2 {main} thrown in /var/www/html/dev/vtlib/Vtiger/Functions.php on line 1512

The reason is the parameters are undefined in the GET request: index.php?module=Quotes&action=GetData&record=undefined&source_module=undefined

The offending code is somewhere in Inventory_Edit_Js and Vtiger_Edit_Js - and I am not sure where the right place to fix it is... The method getRecordDetails() in Vtiger_Edit_Js is obviously going to be called by other code too...