Fix CTS tests for AudioTrack.setPlaybackHeadPosition()

Tests were incorrectly expecting that setPlaybackHeadPosition() did
something meaningful and returned success for a streaming AudioTrack.
AudioTrack implementation now disallows setPlaybackHeadPosition for
streaming. This change fixes the tests to use a static buffer AudioTrack
with setPlaybackHeadPosition().

Bug: 8181114
Change-Id: I61c19b2f75351f18d2b312e065ef601c2cda37a3
1 file changed