[clang] [clang] print correct context for diagnostics suppressed by deduction (PR #125453)

[Matheus Izvekov via cfe-commits]

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@@ -1909,7 +1909,19 @@ class Sema final : public SemaBase {
   /// '\#pragma clang attribute push' directives to the given declaration.
   void AddPragmaAttributes(Scope *S, Decl *D);
 
-  void PrintPragmaAttributeInstantiationPoint();
+  using DiagFuncRef =
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mizvekov wrote:

This is currently used for more things than the InstantiationContext alone, so the name doesn't need to be that specific to it.

`InstantiationContextDiagCallback` doesn't ring like a type to me, FuncRef is more clear in that respect.

https://github.com/llvm/llvm-project/pull/125453