Gf 58362 Scroll threshold has invalidate bounds when list has very small data set.

When DataList has very small data set, page2 does not have any controls. 
In this case, threshold lowerProp is meaningless.
Currently, we don't consider that only page 1 have controls so count could be '0'.

Enyo-DCO-1.1-Signed-off-by: David Um david.um@lge.com