[clang] [llvm] [Clang-Repl] Introduce Error Recovery for Clang-Repl. (PR #223305)

[Vassil Vassilev via cfe-commits]

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@@ -54,6 +54,7 @@
 namespace clang {
 
 class ASTContext;
+class DeclStateReverter;
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vgvassilev wrote:

How does that relate to the `ASTDeclUnmerger`?

https://github.com/llvm/llvm-project/pull/223305