Make Mac build generate both 32-bit and 64-bit code.
Make Mac build generate both 32-bit and 64-bit code.

BUG=http://code.google.com/p/skia/issues/detail?id=524
Review URL: https://codereview.appspot.com/6022057

csulmone/skia,csulmone/skia,csulmone/skia,csulmone/skia