[clang-tools-extra] [clangd] Add new highlighting modifier `CommandLineDefined`. (PR #175495)

[via cfe-commits]

anonymouspc wrote:

Currently, clangd marks all the macros with 1 highlighting-modifier `globalScope`.

I believe it will be beneficial to provide more information, such as `userDefined`, `commandLineDefined`, `platformDefined`. Editors/IDEs can decide how to render these different kinds of macros.

Thanks! :)

https://github.com/llvm/llvm-project/pull/175495