Add linux_chromeos_clang to the list of automatic trybots.

BUG=none
TEST=none


Review URL: https://chromiumcodereview.appspot.com/10833037

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@148600 0039d316-1c4b-4281-b951-d872f2087c98

ash/PRESUBMIT.py

@@ -9,4 +9,4 @@ for more details on the presubmit API built into gcl.
 """
 
 def GetPreferredTrySlaves():
-  return ['linux_chromeos']
+  return ['linux_chromeos', 'linux_chromeos_clang']