[clang] [clang-repl] Lay the basic infrastructure for pretty printing of types (PR #148701)

[Aaron Ballman via cfe-commits]

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@@ -119,9 +119,9 @@ class REPL_EXTERNAL_VISIBILITY Value {
   ~Value();
 
   void printType(llvm::raw_ostream &Out) const;
-  void printData(llvm::raw_ostream &Out) const;
-  void print(llvm::raw_ostream &Out) const;
-  void dump() const;
+  void printData(llvm::raw_ostream &Out);
+  void print(llvm::raw_ostream &Out);
+  void dump();
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AaronBallman wrote:

These APIs are often called from a debugger, I think we really want to leave them `const` so it's safe to use for that use case.

https://github.com/llvm/llvm-project/pull/148701