More updates to build optimization settings.
More updates to build optimization settings.

- Don't pass -s, this doesn't really help anything.  The way we will have
  to generate our final executables is with -g, and then strip them, since
  we will need to keep the original for its symbols.

- Only gc sections in official build.  This might slightly improve release
  link time (at the cost of size).  This allows release to build with GOLD.

Review URL: http://codereview.chromium.org/18846


git-svn-id: http://src.chromium.org/svn/trunk/src@8717 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: eabbb1e92822201ef549d827cbfb3483915d3be1
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