Update yasm to the same version currently used by Chromium.

Update yasm to the same version currently used by Chromium.

* yasm as in Chromium at 5def0de596a472b50c5bfb99ec218c36241e4631.
* I checked that yasm and ffmpeg still appear to build.
* Remove DONT_EMBED_BUILD_METADATA (the main reason for updating yasm).
* Remove yasm's OWNERS file.
* Remove an (apparently) unnecessary entry in .gitignore.

R=jamesr@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/4986f094807d106a9076b17353aaadf144abf2a0

[jamesr, 2016-02-18 19:20:02]

lgtm

[viettrungluu, 2016-02-18 19:23:14]

Description was changed from

==========
Update yasm to the same version currently used by Chromium.

* yasm as in Chromium at 5def0de596a472b50c5bfb99ec218c36241e4631.
* I checked that yasm and ffmpeg still appear to build.
* Remove DONT_EMBED_BUILD_METADATA (the main reason for updating yasm).
* Remove yasm's OWNERS file.
* Remove an (apparently) unnecessary entry in .gitignore.

R=jamesr@chromium.org
==========

to

==========
Update yasm to the same version currently used by Chromium.

* yasm as in Chromium at 5def0de596a472b50c5bfb99ec218c36241e4631.
* I checked that yasm and ffmpeg still appear to build.
* Remove DONT_EMBED_BUILD_METADATA (the main reason for updating yasm).
* Remove yasm's OWNERS file.
* Remove an (apparently) unnecessary entry in .gitignore.

R=jamesr@chromium.org

Committed:
https://chromium.googlesource.com/external/mojo/+/4986f094807d106a9076b17353a...
==========

[viettrungluu, 2016-02-18 19:23:16]

Committed patchset #1 (id:1) manually as
4986f094807d106a9076b17353aaadf144abf2a0 (presubmit successful).