[clang] [clang-format] Add -ConfigFile option (PR #113864)

[Owen Pan via cfe-commits]

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@@ -2102,6 +2108,17 @@ std::error_code parseConfiguration(llvm::MemoryBufferRef Config,
     StyleSet.Add(std::move(DefaultStyle));
   }
   *Style = *StyleSet.Get(Language);
+  std::string ConfigFile;
+  if (!Style->ConfigFile.empty()) {
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owenca wrote:

```suggestion
  if (!Style.InheritsParentConfig && !Style->ConfigFile.empty()) {
```

https://github.com/llvm/llvm-project/pull/113864