[clang] [Clang] Defaults `-Wunicode-whitespace` to an error. (PR #210945)

[Aaron Ballman via cfe-commits]

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@@ -137,8 +137,8 @@ def err_character_not_allowed : Error<
 def err_character_not_allowed_identifier : Error<
   "character <U+%0> not allowed %select{in|at the start of}1 an identifier">;
 def ext_unicode_whitespace : ExtWarn<
-  "treating Unicode character as whitespace">,
-  InGroup<DiagGroup<"unicode-whitespace">>;
+  "treating character <U+%0> as whitespace">,
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AaronBallman wrote:

You are a good person who should feel good for making this diagnostic much more understandable. :-D

https://github.com/llvm/llvm-project/pull/210945