Revert 236644 "[NaCl SDK] Turn off parallel GYP when building na..."

This change has been merged to the 1700 branch, so remove it from trunk.

> [NaCl SDK] Turn off parallel GYP when building nacl_sdk.
> 
> This will make it easier to drover a change to the 1700 branch, instead of
> having to branch native_client to get the real fix (r12324).
> 
> BUG=319564
> R=sbc@chromium.org
> 
> Review URL: https://codereview.chromium.org/62523005

TBR=binji@chromium.org

Review URL: https://codereview.chromium.org/82703004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236775 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236775