Create bp2build converter for cc_shared_library

Have full_cc_library leverage `cc_library_shared` in
its implementation of `cc_library`.

Pull `claim_ownership` into a new `cc_library_common.bzl`,
to share with `cc_library_shared` and `full_cc_library`

Adapt `build/bazel/tests/bionic/compare_libc_stripping.sh`,
`build/bazel/tests/bionic/verify_bionic_outputs.sh`, and
`build/bazel/ci/bp2build.sh` to the new stripped .so naming
scheme; and refactor the first, adding some clear error
checks as well.

Bug: 198241907
Test: cc_library_shared_conversion_test.go
Test: compare_libc_stripping.sh
Test: verify_bionic_outputs.sh
Test: bp2build.sh
Test: mixed_{libc,droid}.sh
Change-Id: I15958ec54bc89183ba96ee5047da11f2e21d3c55