Linux: fix build with gnome-keyring on Aura.

This is upstreaming a Gentoo Linux patch.

BUG=none
R=erg@chromium.org

Review URL: https://codereview.chromium.org/62173003

git-svn-id: http://src.chromium.org/svn/trunk/src/build@235446 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

common.gypi

@@ -545,7 +545,7 @@
         # on gnome-keyring. If that dependency is disabled, no gnome-keyring
         # support will be available. This option is useful
         # for Linux distributions and for Aura.
-        ['chromeos==1 or use_aura==1', {
+        ['OS!="linux" or chromeos==1 or use_aura==1', {
           'use_gnome_keyring%': 0,
         }, {
           'use_gnome_keyring%': 1,