Remove a definition in a weird spot since it's only used on Solaris, which...

Remove a definition in a weird spot since it's only used on Solaris, which nobody is actively porting to right now.

BUG=none
TEST=none
Review URL: http://codereview.chromium.org/5202001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@66578 0039d316-1c4b-4281-b951-d872f2087c98