[libcxxabi] [llvm] [ItaniumDemangle] Add customizable printLeft/printRight APIs to OutputBuffer (PR #133249)

[Richard Smith via llvm-commits]

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@@ -161,14 +179,20 @@ class OutputBuffer {
     DEMANGLE_ASSERT(Pos <= CurrentPosition, "");
     if (N == 0)
       return;
+
+    notifyInsertion(Pos, N);
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zygoloid wrote:

(Likewise.)

https://github.com/llvm/llvm-project/pull/133249