Make sure we upload the LATEST file to google storage, not the master  server, when gs_bucket is used.
Make sure we upload the LATEST file to google storage, not the master 
server, when gs_bucket is used.

Review URL: http://codereview.chromium.org/6559002

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@75694 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build