[clang-tools-extra] [clang-tidy] Header check support for check_clang_tidy.py (PR #175735)

[Baranov Victor via cfe-commits]

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@@ -196,15 +210,36 @@ def get_prefixes(self) -> None:
             )
         assert expect_diagnosis or self.expect_no_diagnosis
 
+    def _sanitize_content(self, text: str) -> str:
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vbvictor wrote:

Could we name this `_remove_filecheck_content` to give more precise meaning.

https://github.com/llvm/llvm-project/pull/175735