[clang] [Format] Fix isStartOfName to recognize attributes (PR #76804)

[Björn Schäpers via cfe-commits]

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@@ -1698,8 +1698,6 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
           /*BasedOnStyle=*/"google",
       },
   };
-  GoogleStyle.AttributeMacros.push_back("GUARDED_BY");
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HazardyKnusperkeks wrote:

I'm open in all directions.

When clang-format does format attribute macros out of the box correctly, that is nice. But I wouldn't put (too much) work into it, if declaring them to clang-format as what they are fixes all misformatting.

Thus I would keep the entries in `AttributeMacros`.

https://github.com/llvm/llvm-project/pull/76804