[clang] [clang-tools-extra] [clang] [diagnostics] Stable IDs for Clang diagnostics (PR #168153)

[Balázs Benics via cfe-commits]

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@@ -147,7 +190,8 @@ VALIDATE_DIAG_SIZE(TRAP)
 const StaticDiagInfoRec StaticDiagInfo[] = {
 // clang-format off
 #define DIAG(ENUM, CLASS, DEFAULT_SEVERITY, DESC, GROUP, SFINAE, NOWERROR,     \
-             SHOWINSYSHEADER, SHOWINSYSMACRO, DEFERRABLE, CATEGORY)            \
+             SHOWINSYSHEADER, SHOWINSYSMACRO, DEFERRABLE, CATEGORY, STABLE_ID, \
+             LEGACY_STABLE_IDS)                                                   \
----------------
steakhal wrote:

clang-format off blocks needs special attention.
```suggestion
             LEGACY_STABLE_IDS)                                                \
```

https://github.com/llvm/llvm-project/pull/168153