NaCl: Update revision in DEPS, r13666 -> r13668

NaCl: Update revision in DEPS, r13666 -> r13668

This pulls in the following Native Client changes:

r13667: (yyanagisawa) Re-enable use of Goma on Windows, except when using the PNaCl toolchain
r13668: (noelallen) Force rebuild on cmd change.

BUG=none
TEST=browser_tests and nacl_integration
CQ_EXTRA_TRYBOTS=tryserver.chromium.linux:linux_rel_precise32,linux_arm_cross_compile,linux_nacl_sdk_build
TBR=bradnelson@chromium.org

Committed: https://crrev.com/87177293362d72095124674372e27ac259d60803
Cr-Commit-Position: refs/heads/master@{#292383}

[Mark Seaborn, 2014-08-28 04:57:42]

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

[Mark Seaborn, 2014-08-28 04:58:11]

The CQ bit was checked by mseaborn@chromium.org

[commit-bot: I haz the power, 2014-08-28 04:59:04]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/mseaborn@chromium.org/513933003/1

[commit-bot: I haz the power, 2014-08-28 05:41:32]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  android_clang_dbg_recipe on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/android_clang_d...)

[commit-bot: I haz the power, 2014-08-28 06:03:22]

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

[commit-bot: I haz the power, 2014-08-28 06:03:23]

Try jobs failed on following builders:
  android_clang_dbg_recipe on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/android_clang_d...)

[Mark Seaborn, 2014-08-28 14:57:00]

The CQ bit was checked by mseaborn@chromium.org

[commit-bot: I haz the power, 2014-08-28 14:57:32]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/mseaborn@chromium.org/513933003/1

[commit-bot: I haz the power, 2014-08-28 15:19:30]

Committed patchset #1 (id:1) as ba2092ce9ac0792098dcca59f9a224e13825dcd5

[tim (not reviewing), 2014-08-28 17:36:24]

A revert of this CL (patchset #1) has been created in
https://codereview.chromium.org/509413002/ by tim@chromium.org.

The reason for reverting is: attempting to fix compile failures..

[commit-bot: I haz the power, 2014-09-10 02:59:35]

Patchset 1 (id:??) landed as
https://crrev.com/87177293362d72095124674372e27ac259d60803
Cr-Commit-Position: refs/heads/master@{#292383}