Audio Latency Tests

Add two tests to gauge audio latency. The cold latency test measures
how fast data can be read from freshly created AudioRecord. The warm
latency test measures how long it takes to record a sound after
creaing an AudioRecord and AudioTrack and waiting a bit.

Change-Id: I06c4990d811ad6815cc1b0d185fab6c45c510f25
9 files changed