Add kCodecPCM_ALAW to histograms.xml

Add kCodecPCM_ALAW to histograms.xml

kCodecPCM_ALAW has been added to media/base/audio_decoder_config.h, but not to histograms.xml

BUG=none

Committed: https://crrev.com/f667c059d40ca1ddaa2d66ee459c550cb546243d
Cr-Commit-Position: refs/heads/master@{#304925}

[servolk, 2014-11-19 22:12:59]

servolk@chromium.org changed reviewers:
+ dalecurtis@chromium.org, ihf@chromium.org

[DaleCurtis, 2014-11-19 22:40:58]

lgtm

[servolk, 2014-11-19 22:43:56]

The CQ bit was checked by servolk@chromium.org

[commit-bot: I haz the power, 2014-11-19 22:44:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/730983004/1

[commit-bot: I haz the power, 2014-11-19 22:51:10]

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

[commit-bot: I haz the power, 2014-11-19 22:51:11]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[Alexei Svitkine (slow), 2014-11-19 23:11:05]

asvitkine@chromium.org changed reviewers:
+ asvitkine@chromium.org

[Alexei Svitkine (slow), 2014-11-19 23:11:06]

lgtm

[servolk, 2014-11-19 23:14:22]

The CQ bit was checked by servolk@chromium.org

[commit-bot: I haz the power, 2014-11-19 23:15:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/730983004/1

[commit-bot: I haz the power, 2014-11-19 23:42:33]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-11-19 23:44:04]

Patchset 1 (id:??) landed as
https://crrev.com/f667c059d40ca1ddaa2d66ee459c550cb546243d
Cr-Commit-Position: refs/heads/master@{#304925}