Patch by Andi Albrecht to fix issue 18: diff of empty added file causes 500 error.
Patch by Andi Albrecht to fix issue 18: diff of empty added file causes
500 error.


git-svn-id: 095a516e186c72f46b708383d0d3f28c2432e8a1@110 e30e9e8f-1b4c-0410-881d-6f13584adfe0

termie/rietveld-mirror,imirkin/rietveld,imirkin/rietveld,termie/rietveld-mirror