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

[Ilya Biryukov 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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ilya-biryukov wrote:

NIT: `llvm::SmallVector<unique_ptr<...>, 1> Consumers`  is a good choice here since we have 1 consumer most of the time.

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