cc: Ref count pixel ref in image decode task.

cc: Ref count pixel ref in image decode task.

This patch ensures that pixel ref will be valid when the image
decode task runs. As it stands right now, there is a possibility
that pixel ref will be accessed after it is freed (by the containing
picture pile).

BUG=305012
R=reveman@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=228506

[vmpstr, 2013-10-11 22:23:40]

Please take a look.

[reveman, 2013-10-14 15:10:07]

lgtm

[commit-bot: I haz the power, 2013-10-14 16:04:43]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/vmpstr@chromium.org/27066005/1

[commit-bot: I haz the power, 2013-10-14 17:58:51]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/vmpstr@chromium.org/27066005/1

[commit-bot: I haz the power, 2013-10-14 18:14:53]

Step "update" is always a major failure.
Look at the try server FAQ for more details.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win&number...

[commit-bot: I haz the power, 2013-10-14 18:17:09]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/vmpstr@chromium.org/27066005/1

[commit-bot: I haz the power, 2013-10-14 19:33:16]

Change committed as 228506