[clang] [Clang] [NFC] Move diagnostics emitting code from `DiagnosticIDs` into `DiagnosticsEngine` (PR #143517)

[Mariya Podchishchaeva via cfe-commits]

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@@ -1046,6 +1046,9 @@ class DiagnosticsEngine : public RefCountedBase<DiagnosticsEngine> {
   bool EmitDiagnostic(const DiagnosticBuilder &DB, bool Force = false);
 
   /// @}
+
+private:
+  void Report(Level DiagLevel, const Diagnostic &Info);
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Fznamznon wrote:

Why not put it right after ProcessDiag on line 1029?

https://github.com/llvm/llvm-project/pull/143517