Revert "Add API for multiple labels in AccesibilityNodeInfo#labe..."

Revert submission 27775536-labeledby

Partial revert: Keeping the flag definition to simplify a later roll-forward, though the flag will be reverted to the initial stage in Gantry.

Reason for revert: Broke UIAutomation

Reverted changes: /q/submissionid:27775536-labeledby

Change-Id: Ifb3aa5e81a5a52507fb9154a275fd4f0431826c2
3 files changed