Revert of Gardening: Revert "Use AudioStreamMonitor to control power save blocking."

Revert of Gardening: Revert "Use AudioStreamMonitor to control power save blocking." (patchset #1 id:1 of https://codereview.chromium.org/562863002/)

Reason for revert:
Bugs should be fixed now... will CQ this revert.

Original issue's description:
> Gardening: Revert "Use AudioStreamMonitor to control power save blocking."
> 
> This reverts commit 484d29dcb45ca362fc9049c37dd3a51e11492f14.
> 
> This patch made media/media-controller-playbackrate.html test crash on DEBUG.
> 
> it crashes at content/browser/web_contents/web_contents_impl.cc:4296 on DCHECK
> Looks like AddMediaPlayerEntry was called twice for the same player_cookie
> 
> It is not clear how it happens due to async nature of the notification.
> The author is sleeping at the moment, so I decided to roll back the patch.
> 
> BUG=
> TBR=dalecurtis@chromium.org
> 
> Committed: https://crrev.com/0381a74131887eb13b5d457cce756fb7066411ea
> Cr-Commit-Position: refs/heads/master@{#294370}

TBR=loislo@chromium.org,jam@chromium.org,miu@chromium.org,scherkus@chromium.org
BUG=43667, 367785
Committed: https://chromium.googlesource.com/chromium/src/+/e63ad8aeff3960724ad2625c7574060e6f608158

[DaleCurtis, 2014-09-12 17:03:37]

Created Revert of Gardening: Revert "Use AudioStreamMonitor to control power
save blocking."

[DaleCurtis, 2014-09-12 17:04:41]

dalecurtis@chromium.org changed reviewers:
+ jam@chromium.org, miu@chromium.org, scherkus@chromium.org

[DaleCurtis, 2014-09-12 17:04:56]

The CQ bit was checked by dalecurtis@chromium.org

[commit-bot: I haz the power, 2014-09-12 17:06:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/569713002/1

[commit-bot: I haz the power, 2014-09-12 19:25:05]

Committed patchset #1 (id:1) as e63ad8aeff3960724ad2625c7574060e6f608158

[commit-bot: I haz the power, 2014-09-12 19:29:36]

Patchset 1 (id:??) landed as
https://crrev.com/bc6572e179e9fea88a60893d428ab8c3b363113a
Cr-Commit-Position: refs/heads/master@{#294630}