[clang] [clang] Use File Location for debug info resolution. (PR #163982)

[Michael Buch via cfe-commits]

Michael137 wrote:

FYI, I'm still investigating the details but internally one of our projects reported a substantial slowdown when compiling with debug-info. Most likely a pathological case with deeply nested macros, but it went from `0.5 s` total runtime to more than a minute. Most of the time being spent in `SourceManager::getFileID`. Will follow-up with more details once I found out

https://github.com/llvm/llvm-project/pull/163982