Mac: Enable fastbuild.
Mac: Enable fastbuild.

BUG=none
TEST=xcode passes -g1 to g++.
TBR=mark
Review URL: http://codereview.chromium.org/2853028

git-svn-id: http://src.chromium.org/svn/trunk/src@51597 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 075e9373ae049a54b8bf0b58aa690bb240f6b402
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser