BHV-9960: Hide scroll columns when 5-way leaving scroller.

Issue
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This is related to a regression from BHV-736 where leaving a scroller via 5-way no longer hides the scroll columns.

Fix
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Because the viewport of the scroll strategy is not spottable, we do an object comparison on the owner of the event originator (which should be the strategy if it is the viewport) and the scroller's strategy.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>