Error on Side-by-side diffs

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Edit one specific C file in my local workspace.
2. Upload a CL.
3. Side-by-side diffs will show a good view on the first click, then "Bad 
content. Try to upload again." for subsequent clicks. Or, for some uploads, it 
always showed "Bad content. Try to upload again.".
But Unified diffs works ok.

What is the expected output? What do you see instead?
Expect side-by-side visual differences. But saw "Bad content. Try to upload 
again."

What browser are you using?  What version? On what operating system?
Gbuntu. Chrome.

At what URL are you accessing Rietveld?  (e.g. codereview.appspot.com)
Please note if you are using the Google Apps Labs version (e.g.
codereview.<yourdomain>).
https://webrtc-codereview.appspot.com/1808005/

*** If you are a Google employee please say so or mail rietveld-admins@
directly. ***
Yes I am.

Please provide any additional information below.

Original issue reported on code.google.com by kma@google.com on 16 Jul 2013 at 4:20

[GoogleCodeExporter]

I filed a similar bug a while ago 
(https://code.google.com/p/rietveld/issues/detail?id=420). Could be related to 
https://code.google.com/p/rietveld/issues/detail?id=28

Original comment by rtoy@chromium.org on 16 Jul 2013 at 4:30

[GoogleCodeExporter]

Oh thank you. I will close this one soon then.
Looks like there's no immediate solution (from issue #28).

Original comment by kma@google.com on 16 Jul 2013 at 4:40