[clang] [clang-tools-extra] [CodeCompletion] Consider header files without extension, if... (PR #166447)

[Björn Schäpers via cfe-commits]

HazardyKnusperkeks wrote:

> > I feel like that’s reasonable; I’m not too familiar w/ the code completion part of Clang so I’ll leave it to someone else to approve this, but it should probably come w/ a release note
> 
> It feels like a fairly large hammer, and I don't know often that structure exists in the wild.

What do you think is large? It may not be that often in the wild, but on the other hand in a directory called `include` I don't think that there are `Makefile`, `README` or similar, what's the argument is, to ignore files without extension by default.

https://github.com/llvm/llvm-project/pull/166447