Fixes BHV-17375

## Issue
`enyo.DataList.scrollToIndex` relies on the bounds of the list to calculate the where to scroll. The bounds are initially set up in the delegate's `rendered` method. When the list is showing initially, this method is called early thereby allowing `scrollToIndex` to function correctly. When the list is hidden, the method is queued up *by priority* to be executed when the list is shown. The current priority has the `rendered` method at a lower priority and therefore called after `scrollToIndex` causing the exception

## Fix
Move the priority of `rendered` before `scrollToIndex`.

Enyo-DCO-1.1-Signed-off-by: Ryan Duffy (ryan.duffy@lge.com)