TIF: Use System.nanoTime() to measure execution durations in sessions

When the wall clock is adjusted to the broadcast time, the duration
measurement in ITvInputSessionWrapper may go wrong. To avoid this, use
System.nanoTime() that doesn't depend on the wall clock.

Bug: 25370822
Change-Id: I2ddb968b5e146500429b82979fe48262bf335993
1 file changed