[clang] [clang-tools-extra] [clang] Extend diagnose_if to accept more detailed warning information (PR #70976)

[Aaron Ballman via cfe-commits]

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@@ -870,7 +872,8 @@ class DiagnosticsEngine : public RefCountedBase<DiagnosticsEngine> {
   /// \param FormatString A fixed diagnostic format string that will be hashed
   /// and mapped to a unique DiagID.
   template <unsigned N>
-  unsigned getCustomDiagID(Level L, const char (&FormatString)[N]) {
+  [[deprecated("Use a CustomDiagDesc instead of a Level")]] unsigned
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AaronBallman wrote:

If we still have uses within tree (which it looks like we do), I think this may cause problems for `-Werror` builds, won't it?

https://github.com/llvm/llvm-project/pull/70976