I see that protobuf was updated to 2.6.0, but none of the 2.6.0 builds in koji have actually succeeded. This has left it in a sad state where the current git contents just doesn't build. Right now protobuf needs to be rebuilt for GCC 5 C++ ABI changes and it's blocking other packages from being built. Please either revert it back to 2.5.0-11 that was the previous working version, or fix the build otherwise.
Looks like current version requires python-google-apputils. I've put up a review request.
I'm working on this.
*** This bug has been marked as a duplicate of bug 1154474 ***