[PATCH] D36261: [clangd] Use multiple working threads in clangd.

[Ilya Biryukov via Phabricator via cfe-commits]

ilya-biryukov added a comment.

Added a test that exercises some multi-threading behaviour. 
It really finds bugs, at least it found a problem that was fixed by https://reviews.llvm.org/D36397. (Will make sure to submit that other change before this one).

As discussed with @klimek, will move to `llvm::ThreadPool` after submitting a fix for it to allow functions with moveable-only arguments to be used there (that's what clangd uses).


https://reviews.llvm.org/D36261