mojo: Starting serialization for python bindings.

mojo: Starting serialization for python bindings.

This is a reland of https://codereview.chromium.org/570563002 with the
gyp build config updated.

R=sdefresne@chromium.org

Committed: https://crrev.com/08fb34f917c8e84c0ad94e326b8ae9e81c5d3d90
Cr-Commit-Position: refs/heads/master@{#295038}

[qsr, 2014-09-16 08:46:58]

The change from the reverted version is in the gyp file.

[sdefresne, 2014-09-16 08:58:25]

lgtm

[qsr, 2014-09-16 09:21:24]

The CQ bit was checked by qsr@chromium.org

[commit-bot: I haz the power, 2014-09-16 09:22:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/571353002/20001

[commit-bot: I haz the power, 2014-09-16 10:21:06]

Committed patchset #2 (id:20001) as 60f5ced1ac7e763669d0d15f6134a6b01352ae12

[commit-bot: I haz the power, 2014-09-16 10:22:21]

Patchset 2 (id:??) landed as
https://crrev.com/08fb34f917c8e84c0ad94e326b8ae9e81c5d3d90
Cr-Commit-Position: refs/heads/master@{#295038}