[clang] [clang-repl] Simplify the value printing logic to enable out-of-process. (PR #107737)

[Aaron Ballman via cfe-commits]

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@@ -53,6 +53,7 @@ class MultiplexConsumer : public SemaConsumer {
 public:
   // Takes ownership of the pointers in C.
   MultiplexConsumer(std::vector<std::unique_ptr<ASTConsumer>> C);
+  MultiplexConsumer(std::unique_ptr<ASTConsumer> C);
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AaronBallman wrote:

This feels unnecessary because you should be able to do `MultiplexConsumer M({std::move(ptr)});` right?

https://github.com/llvm/llvm-project/pull/107737