Can we have different times for mute/unmute and new stream?  mut/unmute can be longer than new stream.

We also need to be careful that we start ramping asap even if it's a high latency stream.  If there is already 40ms of audio queued then we have to play that before ramping which may make the ramp feel longer than it is.

https://chromium-review.googlesource.com/472327 posted.

The new durations:

RAMP_UNMUTE_DURATION_SECS = 0.5;
RAMP_NEW_STREAM_DURATION_SECS = 0.01;
RAMP_MUTE_DURATION_SECS = 0.1;

Keep unmute duration to 0.5 and tune the ramp duration for new stream and mute shorter.

Thanks!

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/adhd/+/d4c8bcdbc8df5a1e6c0929e3747f39a9a89dd075

commit d4c8bcdbc8df5a1e6c0929e3747f39a9a89dd075
Author: Cheng-Yi Chiang <cychiang@chromium.org>
Date: Mon Apr 17 05:39:02 2017

CRAS: iodev - Tune the ramp duration

Set ramp duration for new stream to 0.01 so user does not miss the
start of new stream.
Set ramp duration for mute to 0.1 so mute can happen sooner.

BUG= chromium:709323 
TEST=make check
TEST=check ramp duration for new stream is almost not noticeable.
TEST=check ramp duration for mute is much shorter than before.

Change-Id: If74d094aad11748e3198e8e9402a4d4de9631694
Reviewed-on: https://chromium-review.googlesource.com/472327
Commit-Ready: Cheng-Yi Chiang <cychiang@chromium.org>
Tested-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-by: Chinyue Chen <chinyue@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>

[modify] https://crrev.com/d4c8bcdbc8df5a1e6c0929e3747f39a9a89dd075/cras/src/tests/iodev_unittest.cc
[modify] https://crrev.com/d4c8bcdbc8df5a1e6c0929e3747f39a9a89dd075/cras/src/server/cras_iodev.c

Verified in Chrome OS 9565.0.0;60.0.3102.0.