Revert of Modifies size of ring buffer in shared memory on the audio capture side

Revert of Modifies size of ring buffer in shared memory on the audio capture side (patchset #3 id:40001 of https://codereview.chromium.org/1254793002/ )

Reason for revert:
This was an speculative change and should now be reverted. There is no sign that this change would fix or improve the issue.

Original issue's description:
> Modifies size of ring buffer in shared memory on the audio capture side.
>
> We have seen reports in Chrome where segments of repeated input audio has
> damaged AEC performance in WebRTC clients. This patch is an attempt to limit
> the number of possible places in Chrome where such a patter could be created.
>
> It is a speculative patch and the idea is that it should live in Canary
> for a while so we can see if there are any positive effects.
>
> TBR=tommi
> BUG=b/13976602
> TEST=manual tests of different WebRTC clients running in loopback to ensure that no
> audio artifacts can be detected
>
> Committed: https://crrev.com/bda4fc7018c3ce93d88b74461a065f9eaf0b8b5f
> Cr-Commit-Position: refs/heads/master@{#340261}

TBR=tommi@chromium.org,dalecurtis@chromium.org,henrika@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=b/13976602

Committed: https://crrev.com/1e8d8de4a6cabcd7b908bbb794b1ce50d7cbd7a6
Cr-Commit-Position: refs/heads/master@{#342336}

[Henrik Grunell, 2015-08-07 11:41:37]

Created Revert of Modifies size of ring buffer in shared memory on the audio
capture side

[commit-bot: I haz the power, 2015-08-07 11:41:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1277173002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1277173002/1

[commit-bot: I haz the power, 2015-08-07 11:42:05]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-08-07 11:42:51]

Patchset 1 (id:??) landed as
https://crrev.com/1e8d8de4a6cabcd7b908bbb794b1ce50d7cbd7a6
Cr-Commit-Position: refs/heads/master@{#342336}