[clang] [Clang] Fix FixIt for implicit-int diagnostics. (PR #179356)

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https://github.com/Sirraide commented:

Yeah, I think checking for the first declarator in `ConvertDeclSpecToType()` should work; the other places can be left as-is I think (e.g. `Parser::ParseFunctionDefinition` is fine since function definitions can't be part of a decl group anyway).



https://github.com/llvm/llvm-project/pull/179356