Remove the host_override option to upload.py.  This sets the Host header, which for some reason, trips the new internal proxy.
Review URL: http://codereview.chromium.org/1798008

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@45833 0039d316-1c4b-4281-b951-d872f2087c98