[clang] [clang-format] Add DiagHandler for getStyle function (PR #91317)

[Owen Pan via cfe-commits]

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@@ -4027,12 +4031,10 @@ Expected<FormatStyle> getStyle(StringRef StyleName, StringRef FileName,
   // Reset possible inheritance
   Style.InheritsParentConfig = false;
 
-  auto dropDiagnosticHandler = [](const llvm::SMDiagnostic &, void *) {};
-
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owenca wrote:

Sorry! We do need it.

https://github.com/llvm/llvm-project/pull/91317