Add missing miu@ to OWNERS files for Cast Streaming, and pruning.

Add missing miu@ to OWNERS files for Cast Streaming, and pruning.

Removed pwestin@ and mikhal@ from OWNERS files, since they have been off
the project for over a year.

Committed: https://crrev.com/707a194f8e53483081da0f9166619216cdcf7f5e
Cr-Commit-Position: refs/heads/master@{#324300}

[miu, 2015-04-08 20:46:37]

miu@chromium.org changed reviewers:
+ dalecurtis@chromium.org

[miu, 2015-04-08 20:46:38]

PTAL.  Feel free to CQ if LGTY.

[DaleCurtis, 2015-04-08 20:48:56]

The CQ bit was checked by dalecurtis@chromium.org

[DaleCurtis, 2015-04-08 20:48:57]

lgtm

[commit-bot: I haz the power, 2015-04-08 20:50:56]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1074573002/1

[commit-bot: I haz the power, 2015-04-08 22:58:58]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-08 23:00:21]

Patchset 1 (id:??) landed as
https://crrev.com/707a194f8e53483081da0f9166619216cdcf7f5e
Cr-Commit-Position: refs/heads/master@{#324300}