BHV-15102: Display SCRIM when popup is shown

**Issue:** 
When multiple popup(having animation) are shown and hidden alternatively, the SCRIM behind the popup is hidden. The last popup which was made hidden, triggers the animation end event which hides the SCRIM.
**Fix:** 
SCRIM is made visible when the popup showing animation is complete.

Enyo-DCO-1.1-Signed-off-by: Anish Ramesan <anish.ramesan@lge.com>
yeah @aarontam this line is required because there is a possibility where there can be a popup and no scrim. To handle such cases this line is added.  Explanation to add this line is given under jira ticket comments by @anishramesan. you can see more in followup comments. Thankyou.