Exception occurred in Group control

Issue:
When components are destroyed dynamically in side a group control,
exception observed inside the activeChanged function.

Fix:
checking whether the component is destroyed or not.

Enyo-DCO-1.1-Signed-off-by: Srinivas V srinivas.v@lge.com
Fixed the offsetTop/offsetLeft properties and background-sizing so sprites appear the correct size.

Enyo-DCO-1.1-Signed-off-by: Blake Stephens <blake.stephens@lge.com>
Merge pull request #844 from enyojs/BHV-13443-blakestephens

BHV-13443: Fixed the offsetTop/offsetLeft properties and background-sizing
Reviewed - by Art Dahm (art.dahm@lge.com)
Merge pull request #842 from enyojs/BHV-13593-srinvasv

Exception occurred in Group control