Revert 252593 "Mojo: Write some tests for public/system/macros.h."

> Mojo: Write some tests for public/system/macros.h.
> 
> I really set out to also write no-compile tests, but they're currently totally
> disabled. :(
> 
> R=sky@chromium.org
> 
> Review URL: https://codereview.chromium.org/175343002

TBR=viettrungluu@chromium.org

Review URL: https://codereview.chromium.org/169433003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252596 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252596