[clang] [WIP] Implement `-dump-deserialized-declaration-ranges` flag. (PR #133910)

[Viktoriia Bakalova via cfe-commits]

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@@ -121,6 +267,26 @@ FrontendAction::CreateWrappedASTConsumer(CompilerInstance &CI,
   if (!Consumer)
     return nullptr;
 
+  std::vector<std::unique_ptr<ASTConsumer>> Consumers;
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VitaNuo wrote:

The constructor of `MultiplexConsumer` won't take a `SmallVector`.

https://github.com/llvm/llvm-project/pull/133910