Revert of Mojo+NaCl: Move generated code to mojo/nacl.

Revert of Mojo+NaCl: Move generated code to mojo/nacl. (patchset #1 id:1 of https://codereview.chromium.org/896243003/)

Reason for revert:
Caused build failures on mac bots. Not sure why it failed there but not on the CQ.

Original issue's description:
> Mojo+NaCl: Move generated code to mojo/nacl.
>
> This change moves generated code for Mojo support in NaCl from mojo/monacl to
> mojo/nacl. This makes the target directory more consistent across GYP and GN
> builds.
>
> An upcoming change for IRT support will generate a header, which will need a
> consistent path (relative to include_dirs) across build systems.
>
> BUG=454466
>
> Committed: https://crrev.com/99cdffdb116cf608630600bbbf66a37fcf16695e
> Cr-Commit-Position: refs/heads/master@{#314591}

TBR=ncbray@chromium.org,jamesr@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=454466
Committed: https://crrev.com/8ebfc680baa6179dcb6d4bd9438add5f1e16ba3e
Cr-Commit-Position: refs/heads/master@{#314597}

[teravest, 2015-02-04 18:53:13]

Created Revert of Mojo+NaCl: Move generated code to mojo/nacl.

[commit-bot: I haz the power, 2015-02-04 18:53:37]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/900983002/1

[commit-bot: I haz the power, 2015-02-04 18:54:35]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-04 18:55:40]

Patchset 1 (id:??) landed as
https://crrev.com/8ebfc680baa6179dcb6d4bd9438add5f1e16ba3e
Cr-Commit-Position: refs/heads/master@{#314597}