Revert the change to encode the uploaded content as UTF-8.
Revert the change to encode the uploaded content as UTF-8.

The change made to RC1 for fixing diff uploading in some cases actually
broke things. The content length was no longer correct, if we even could
encode to UTF-8. We now upload the raw bytes once again.

halvorlu/rbtools,blair/pkg-rbtools,haosdent/rbtools,reviewboard/rbtools,reviewboard/rbtools,bcelary/rbtools,beol/rbtools,beol/rbtools,clach04/rbtools,Khan/rbtools,reviewboard/rbtools,datjwu/rbtools,halvorlu/rbtools,clach04/rbtools_0.4.1,haosdent/rbtools,1tush/rbtools,datjwu/rbtools,datjwu/rbtools,clach04/old_rbtools_0.3.2,davidt/rbtools,davidt/rbtools,Khan/rbtools,beol/rbtools,haosdent/rbtools,halvorlu/rbtools,davidt/rbtools