[clang-tools-extra] [clangd] Propagate context into stdlib indexing thread (PR #87611)

[Sam McCall via cfe-commits]

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@@ -112,7 +112,10 @@ struct UpdateIndexCallbacks : public ParsingCallbacks {
                  // Index outlives TUScheduler (declared first)
                  FIndex(FIndex),
                  // shared_ptr extends lifetime
-                 Stdlib(Stdlib)]() mutable {
+                 Stdlib(Stdlib),
+                 // We have some FS implementations that rely on infomration in
+                 // the context.
+                 Ctx(Context::current().clone())]() mutable {
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sam-mccall wrote:

this doesn't work - need to actually WithContext it inside the body

https://github.com/llvm/llvm-project/pull/87611