[clang-tools-extra] [clang-doc] Refactor error handling to use ExitOnError (PR #141699)

[Paul Kirth via cfe-commits]

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@@ -245,10 +247,32 @@ sortUsrToInfo(llvm::StringMap<std::unique_ptr<doc::Info>> &USRToInfo) {
   }
 }
 
+llvm::Error handleMappingPhaseErrors(llvm::Error Err,
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ilovepi wrote:

This should be `static`. `handleMappingFailures()` makes more sense to me as an API name. Since IgnoreMappingFailures isn't a local, so you don't need to pass it in, since its visible to the whole file.

https://github.com/llvm/llvm-project/pull/141699