Added helper for upload/download of canned nexes. Cleaned up the rest of script to reduce code duplication.
Added helper for upload/download of canned nexes.
Cleaned up the rest of script to reduce code duplication.

BUG=

Review URL: https://codereview.chromium.org/11361204

git-svn-id: 721b910a23eff8a86f00c8fd261a7587cddf18f8@10263 fcba33aa-ac0c-11dd-b9e7-8d5594d729c2

sbc100/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client,nacl-webkit/native_client,nacl-webkit/native_client,nacl-webkit/native_client,sbc100/native_client,nacl-webkit/native_client,sbc100/native_client,nacl-webkit/native_client