Give the clang upload bots shorter names.
Currently, git fails to delete files on these bots because path names
are too long (on Windows), and the bot / checkout name is part of the
path. Our other bots don't have this problem, so try giving the bot
a shorter name (and rename the non-Win bots for consistency).
BUG=
600465
Committed:
http://src.chromium.org/viewvc/chrome?view=rev&revision=299707