Bhv 10793 Resolve timing issue that can be occurred from sequential key input

Issue
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Sometime last key input is lost and there is not following panel transition after first panel move. 
Just in some specific cases.

To reproduce it, press right first then press left with having a little gap.
More precisely when panel is moving to right, press left. 
What is your expected? Yes. It should move to left.
However there is no more transition.

Cause
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Currently queuedIndex is only get a value when setIndex() is executed.
If next key input is occurred after setIndex() is executed, this key input will be lost.

Fix
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Move updating queuedIndex into spotlight handlers.