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

[kadir çetinkaya via cfe-commits]

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@@ -57,7 +61,7 @@ class ModuleDependencyScanner {
   /// a global module dependency scanner to monitor every file. Or we
   /// can simply require the build systems (or even the end users)
   /// to provide the map.
-  void globalScan();
+  void globalScan(CommandProvider const &Provider);
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kadircet wrote:

we don't really use east-const in clangd related code (also other places below)

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