ENYO-874: Settings app has a problem of not showing scroller content under fittable layout
ENYO-874: Settings app has a problem of not showing scroller content under fittable layout

- Fix oPanels to this.getPanels() because oPanels is not including whole panels but new panels which is created.
- Add clamp on lastIndex to cover negative options.targetIndex case.
- Remove else case which is adding +1 and remove -1 from lastIndex initial value.

DCO-1.1-Signed-Off-By: Kunmyon Choi kunmyon.choi@lge.com

mcanthony/moonstone,mcanthony/moonstone,enyojs/moonstone,mcanthony/moonstone