[clangd] Clean the cache of file statuses on vscode-clangd when clangd crashes.

Summary:
Clear the cached file statuses, otherwise we will leave some garbage texts on
the status bar when clangd crashes.

Reviewers: ilya-biryukov

Subscribers: ioeric, MaskRay, jkorous, arphaman, kadircet, cfe-commits

Differential Revision: https://reviews.llvm.org/D56540

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@352049 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed