[clang-tools-extra] [clangd] Make clangd-indexer respect .clangd configuration files (PR #214951)

[Nathan Ridge via cfe-commits]

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@@ -997,26 +990,10 @@ clangd accepts flags on the commandline, and in the CLANGD_FLAGS environment var
 
   RealThreadsafeFS TFS;
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HighCommander4 wrote:

nit: move this above the declaration of `Opts` (rationale: `Opts` now owns the providers which hold a reference to `TFS`, so `TFS` should outlive it)

https://github.com/llvm/llvm-project/pull/214951