Reduce LS_INFO spam from voice_engine/.

Reduce LS_INFO spam from voice_engine/.

Removes ShouldIgnoreTrace from WebRtcVoiceEngine and removes the spammy
log instances instead. Also removes trace-style logging from getters
(::GetLocalSSRC() for instance would print what SSRC it got, spamming
the log).

BUG=
R=henrika@webrtc.org

Committed: https://crrev.com/d5c75b1a0ba1548d3561109e3e5e63757509e9ae
Cr-Commit-Position: refs/heads/master@{#10028}

[pbos-webrtc, 2015-09-22 15:58:53]

PTAL, these did remove the log lines you sent in a mail. I'm not sure these are
all of them, and I'm not sure why they started appearing all of a sudden (maybe
LS_INFO hasn't been displayed?).

[henrika_webrtc, 2015-09-23 07:02:51]

Many thanks Peter!

LGTM

[pbos-webrtc, 2015-09-23 09:29:52]

The CQ bit was checked by pbos@webrtc.org

[commit-bot: I haz the power, 2015-09-23 09:30:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1347353004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1347353004/1

[commit-bot: I haz the power, 2015-09-23 09:53:24]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-09-23 09:53:24]

Try jobs failed on following builders:
  win_compile_dbg on tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/win_compile_dbg/builds/43)
  win_drmemory_light on tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/win_drmemory_light/buil...)
  win_rel on tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/win_rel/builds/9701)

[pbos-webrtc, 2015-09-23 11:14:28]

The CQ bit was checked by pbos@webrtc.org

[commit-bot: I haz the power, 2015-09-23 11:14:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1347353004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1347353004/1

[pbos-webrtc, 2015-09-23 11:24:49]

Committed patchset #1 (id:1) manually as
d5c75b1a0ba1548d3561109e3e5e63757509e9ae (presubmit successful).

[commit-bot: I haz the power, 2015-09-23 11:24:55]

Patchset 1 (id:??) landed as
https://crrev.com/d5c75b1a0ba1548d3561109e3e5e63757509e9ae
Cr-Commit-Position: refs/heads/master@{#10028}