Browser source tarball size again (hopefully transient)

While I still hope that this is just a minor transient glitch in the tarball's creation process, chromium's source tar size has recently increased from ~327 MiB to 1367 MiB in 47.0.2526.106. Yes, that's correct, we are talking 1.33 GiB now. A quick look indicates that it contains lots of binary files for multiple architectures. Hopefully this gets removed again in upcoming releases. Source tarballs should be just that: source.