Increase WebRTC socket send buffer to 256k.

Increase WebRTC socket send buffer to 256k.

WebRTC has a throttling mechanism to ensure we don't push too much data into the system socket. The buffer size doesn't seem to be set correctly and it was experienced video freeze from time to time as the throttling mechanism kicks in too frequently and causes video packets dropped, even though system still has more capacity to handle it.

BUG=427555
Committed: https://crrev.com/08114182ecdd79be715812199abb1da33a6bae74
Cr-Commit-Position: refs/heads/master@{#301580}

[guoweis2, 2014-10-27 23:55:56]

guoweis@google.com changed reviewers:
+ guoweis@google.com, juberti@chromium.org

[guoweis2, 2014-10-27 23:55:57]

PTAL

[guoweis2, 2014-10-27 23:57:31]

guoweis@google.com changed reviewers:
+ davidben@chromium.org

[guoweis2, 2014-10-27 23:57:32]

davidben@chromium.org: Please OWNER review changes in this CL.

[davidben, 2014-10-28 00:12:02]

lgtm

[guoweis2, 2014-10-28 00:35:16]

The CQ bit was checked by guoweis@google.com

[commit-bot: I haz the power, 2014-10-28 00:41:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/678103003/1

[juberti2, 2014-10-28 00:42:03]

lgtm

[commit-bot: I haz the power, 2014-10-28 01:15:18]

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

[commit-bot: I haz the power, 2014-10-28 01:15:18]

Try jobs failed on following builders:
  mac_chromium_rel on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel/...)

[guoweis2, 2014-10-28 01:17:11]

The CQ bit was checked by guoweis@google.com

[commit-bot: I haz the power, 2014-10-28 01:18:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/678103003/1

[guoweis2, 2014-10-28 06:23:15]

The CQ bit was unchecked by guoweis@google.com

[guoweis2, 2014-10-28 06:23:16]

The CQ bit was checked by guoweis@google.com

[commit-bot: I haz the power, 2014-10-28 06:23:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/678103003/1

[commit-bot: I haz the power, 2014-10-28 06:56:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-28 06:57:22]

Patchset 1 (id:??) landed as
https://crrev.com/08114182ecdd79be715812199abb1da33a6bae74
Cr-Commit-Position: refs/heads/master@{#301580}