libpng: update upstream version 1.6.12 -> 1.6.20

libpng: update upstream version 1.6.12 -> 1.6.20

Committed: https://chromium.googlesource.com/webports/+/97c086f9835058b64f770689a18728292aa62672

[Sam Clegg, 2016-01-15 00:26:40]

sbc@chromium.org changed reviewers:
+ bradnelson@chromium.org

[Sam Clegg, 2016-01-15 00:29:38]

The CQ bit was checked by sbc@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-01-15 00:29:40]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1585303003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1585303003/1

[bradnelson, 2016-01-15 00:36:50]

lgtm

[commit-bot: I haz the power, 2016-01-15 00:39:48]

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

[commit-bot: I haz the power, 2016-01-15 00:39:49]

Dry run: Try jobs failed on following builders:
  webports-linux-clang-2 on tryserver.nacl (JOB_FAILED,
http://build.chromium.org/p/tryserver.nacl/builders/webports-linux-clang-2/bu...)
  webports-linux-glibc-0 on tryserver.nacl (JOB_FAILED,
http://build.chromium.org/p/tryserver.nacl/builders/webports-linux-glibc-0/bu...)

[Sam Clegg, 2016-01-19 20:46:12]

The CQ bit was checked by sbc@chromium.org

[commit-bot: I haz the power, 2016-01-19 20:46:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1585303003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1585303003/1

[commit-bot: I haz the power, 2016-01-19 23:17:29]

Description was changed from

==========
libpng: update upstream version 1.6.12 -> 1.6.20
==========

to

==========
libpng: update upstream version 1.6.12 -> 1.6.20

Committed:
https://chromium.googlesource.com/webports/+/97c086f9835058b64f770689a1872829...
==========

[commit-bot: I haz the power, 2016-01-19 23:17:30]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/webports/+/97c086f9835058b64f770689a1872829...