Bhv 11099 Has improper position for disabled control.

Issue
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If tooltip is showing on disabled control, it could not calculate its position

Cause
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Current position calculation of tooltip is based on enyo.Spotlight.getCurrent()
However disabled control could not have spotlight focus. It makes problem.

Fix
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If activator is disabled, we will use decorator's bounds as activator's
because decorator could cover activator's space.