Revert "Set input thread priority to RT"

This reverts commit 930f77b0.

Reason for revert: DroidMonitor: Potential culprit for http://b/376665573 - verifying through ABTD before revert submission. This is part of the standard investigation process, and does not mean your CL will be reverted.

Change-Id: I9b9914703946f1eb4e40e779aa9cb5154ea108d3