[clang-tools-extra] [clangd] Support .clangd command line modifications for C++ modules (PR #122606)

[Petr Polezhaev via cfe-commits]

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@@ -32,9 +32,6 @@ namespace {
 /// interfere with each other.
 class ModuleDependencyScanner {
 public:
-  using CommandProvider =
-      llvm::unique_function<void(tooling::CompileCommand &, PathRef) const>;
-
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petr-polezhaev wrote:

Or `using CommandMangler = ProjectModules::CommandMangler`?

https://github.com/llvm/llvm-project/pull/122606