This change moves almost everything in the `upb/` directory up one level, so
that for example `upb/upb/generated_code_support.h` becomes just
`upb/generated_code_support.h`. The only exceptions I made to this were that I
left `upb/cmake` and `upb/BUILD` where they are, mostly because that avoids
conflict with other files and the current locations seem reasonable for now.
The `python/` directory is a little bit of a challenge because we had to merge
the existing directory there with `upb/python/`. I made `upb/python/BUILD` into
the BUILD file for the merged directory, and it effectively loads the contents
of the other BUILD file via `python/build_targets.bzl`, but I plan to clean
this up soon.
PiperOrigin-RevId: 568651768
A couple weeks ago we moved upb into the protobuf Git repo, and this change
continues the merger of the two repos by making them into a single Bazel repo.
This was mostly a matter of deleting upb's WORKSPACE file and fixing up a bunch
of references to reflect the new structure.
Most of the changes are pretty mechanical, but one thing that needed more
invasive changes was the Python script for generating CMakeLists.txt,
make_cmakelists.py. The WORKSPACE file it relied on no longer exists with this
change, so I updated it to hardcode the information it needed from that file.
PiperOrigin-RevId: 564810016
This is the second attempt to fix our Git history. This should allow
"git blame" to work correctly in the upb/ directory even though our
automation unexpectedly blew away that directory.
