download_gold_plugin.py: Redirect stderr to /dev/null when calling gsutil.

build/download_gold_plugin.py

 #!/usr/bin/env python
 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Script to download LLVM gold plugin from google storage."""
 
 import json
 import os
 import shutil
@@ skipping 17 matching lines @@
 CLANG_REVISION = os.popen(CLANG_UPDATE_PY + ' --print-revision').read().rstrip()
 
 CLANG_BUCKET = 'gs://chromium-browser-clang/Linux_x64'
 
 def main():
   targz_name = 'llvmgold-%s.tgz' % CLANG_REVISION
   remote_path = '%s/%s' % (CLANG_BUCKET, targz_name)
 
   os.chdir(LLVM_BUILD_PATH)
 
+  # TODO(pcc): Fix gsutil.py cp url file < /dev/null 2>&0
+  # (currently aborts with exit code 1,
+  # https://github.com/GoogleCloudPlatform/gsutil/issues/289) or change the
+  # stdin->stderr redirect in update.py to do something else (crbug.com/494442).
   subprocess.check_call(['python', GSUTIL_PATH,
-                         'cp', remote_path, targz_name])
+                         'cp', remote_path, targz_name],
+                        stderr=open('/dev/null', 'w'))
   subprocess.check_call(['tar', 'xzf', targz_name])
   os.remove(targz_name)
   return 0
 
 if __name__ == '__main__':
   sys.exit(main())