[clang] [NFC][clang] Remove superfluous header files after refactor in #132252 (PR #132495)

[Erich Keane via cfe-commits]

https://github.com/erichkeane commented:

How'd you manage to find the right ones?  IMO we should be using include-what-you-use on these to make sure we get it right (if you have already, disregard this).

Also, can you share before-split/after-split/after-this build time benchmarks?  Does this get us back to reasonable?


https://github.com/llvm/llvm-project/pull/132495