[clang] [clang-tools-extra] [flang] [lldb] [llvm] [clang] Refactor option-related code from clangDriver into new clangOptions library (PR #163659)

[Steven Wu via llvm-commits]

cachemeifyoucan wrote:

> I’d be happy to do the formatting modernization, just want to confirm what’s expected. Should this mainly mean running clang-format over all affected headers (not just the diff) and cleaning up unused includes, or also things like updating comments, namespace usage, etc ...?

I will not worry about this. Those are things won't caught by clang-format (there is a bot to guard clang-format changes).

>It seems that this PR is requiring downstream users who link with clangDriver to also link with clangOptions. Because of this, I don't consider this to be an NFC change, and would like to see a release note in "Potentially breaking changes" section.

To verify this, I suggest to do a build with CMake option `BUILD_SHARED_LIBS=On` to verify the dependencies are all correct.

https://github.com/llvm/llvm-project/pull/163659