[clang] [clang-tools-extra] [clang][tidy] Ensure rewriter has the correct CWD (PR #67839)

[Piotr Zegar via cfe-commits]

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@@ -227,6 +227,14 @@ class ErrorReporter {
           llvm::errs() << "Can't apply replacements for file " << File << "\n";
         }
       }
+
+      auto BuildDir = Context.getCurrentBuildDirectory();
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PiotrZSL wrote:

I think you may need to do what is done in handleErrors method.
Simply remember old value, change new value to build directory, and after call to overwriteChangedFiles restore it.
By default getCurrentWorkingDirectory should return actually current working directory.

https://github.com/llvm/llvm-project/pull/67839