Enable webkit.gyp compiler warnings on mac only.

Linux fails in opt build due to strict aliasing in WebCore.

BUG=21140

Review URL: http://codereview.chromium.org/215040


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@26831 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed