[clang] [Coverage] Fix assertion failure when a -isystem header invokes a user macro (PR #195427)

[NAKAMURA Takumi via cfe-commits]

https://github.com/chapuni approved this pull request.

Thanks. This works. Sorry for the delay.

You may merge this. I know the deadline toward 22.1.7 is approaching.
Then I will write excuses to the preceding request #181319.

I have confirmed both #181319 and this satisfies both testcases each other.

Could you close your #195422 as duplicate? I would be happy if we could respect the preceding reporter #179316.

I didn't notice this issue since I was running my testcases with -Asserts.

https://github.com/llvm/llvm-project/pull/195427