Easiest way to find out is to look at the file source and see what is raising the warning.
i.e. line 11505 of ext-all-dev.js if you click on the blue file name it should open the source file in debugger at the line position.
My guess is you maybe in your app somewhere using the functions - determineScrollbars or invalidateScroller on Ext.panel.Table
These two methods have been depreciated - hence the warning.