Revert r1819 for now, it broke the mac bots.

Failing tests are at
http://build.chromium.org/p/tryserver.nacl/builders/gyp-mac/builds/1478

Failed the following 4 tests:
        test/ios/gyptest-app-ios.py
        test/ios/gyptest-archs.py
        test/ios/gyptest-per-config-settings.py
        test/mac/gyptest-framework-dirs.py



git-svn-id: http://gyp.googlecode.com/svn/trunk@1823 78cadc50-ecff-11dd-a971-7dbc132099af