media: Make |web_encrypted_media_client_| a scoped_ptr.

media: Make |web_encrypted_media_client_| a scoped_ptr.

In the current implementation |web_encrypted_media_client_| is leaked.

BUG=450777
Committed: https://crrev.com/430baee98c51d0d733f6262b2c9f607d81402361
Cr-Commit-Position: refs/heads/master@{#312569}

[xhwang, 2015-01-21 22:22:47]

xhwang@chromium.org changed reviewers:
+ jrummell@chromium.org, nasko@chromium.org

[xhwang, 2015-01-21 22:22:47]

jrummell: PTAL
nasko: Please OWNERS review.
ddorwin: FYI

[jrummell, 2015-01-21 23:20:23]

lgtm

[nasko, 2015-01-21 23:41:50]

LGTM

[xhwang, 2015-01-22 00:43:17]

The CQ bit was checked by xhwang@chromium.org

[commit-bot: I haz the power, 2015-01-22 00:45:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/865683004/20001

[commit-bot: I haz the power, 2015-01-22 02:05:18]

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

[commit-bot: I haz the power, 2015-01-22 02:05:19]

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

[xhwang, 2015-01-22 05:05:00]

The CQ bit was checked by xhwang@chromium.org

[commit-bot: I haz the power, 2015-01-22 05:06:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/865683004/20001

[commit-bot: I haz the power, 2015-01-22 05:06:19]

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

[commit-bot: I haz the power, 2015-01-22 05:06:20]

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

[xhwang, 2015-01-22 05:33:05]

The CQ bit was checked by xhwang@chromium.org

[commit-bot: I haz the power, 2015-01-22 05:33:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/865683004/20001

[commit-bot: I haz the power, 2015-01-22 05:46:47]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-01-22 05:48:40]

Patchset 2 (id:??) landed as
https://crrev.com/430baee98c51d0d733f6262b2c9f607d81402361
Cr-Commit-Position: refs/heads/master@{#312569}