BHV-19184: Prevent pointer events from IntegerPicker's client area.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>
Merge pull request #1830 from enyojs/BHV-19184-aarontam-2.5

BHV-19184: Prevent pointer events from IntegerPicker's client area.