[clang] [clang] [Serialization] No transitive change for MacroID and PreprocessedEntityID (PR #166346)

[Jan Svoboda via cfe-commits]

jansvoboda11 wrote:

Also, can you please compile real-world modules (e.g. libc++) and show how this affects the PCM size?

https://github.com/llvm/llvm-project/pull/166346