BHV-10443 : Moonstone Component Bug for ExpandableListItem.

Bug: Although header text area is tapped with 5-way button, the drawer does not open. This is regression of BHV-1356
Fix: SpotlightFocus and tap event handling point are moved from header component to headerContainer component

DCO-1.1-Signed-Off-By: SoonGil Choi soongil.choi@lge.com
Merge pull request #1378 from enyojs/GF-63358-soongil

BHV-10443 : Moonstone Component Bug for ExpandableListItem.

Looks good!

Reviewed-by: Aaron Tam (aaron.tam@lge.com)