Roll cros_system_api to 3fabe200 for new cras property constants.

BUG=160311
TBR=ben

Review URL: https://codereview.chromium.org/13998026

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@194499 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -552,7 +552,7 @@ deps_os = {
     # For Linux and Chromium OS.
     "src/third_party/cros_system_api":
       Var("chromiumos_git") + "/platform/system_api.git" +
-      "@5d39f60ce99c9133ff5932446ba46a51bf0c2b70",
+      "@3fabe2002eae665cd108685376d6a07ccbebe533",
 
     # Note that this is different from Android's freetype repo.
     "src/third_party/freetype2/src":