[clang] Fix preprocessed block comment newline on windows containing extra carriage return (PR #205084)

[Joe Kirchoff via cfe-commits]

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@@ -0,0 +1,4 @@
+// RUN: %python -c "open(r'%t.h','wb').write(open(r'%S/Inputs/comment_save_crlf.h','rb').read().replace(b'\r\n',b'\n').replace(b'\n',b'\r\n'))"
+// RUN: %python -c "import sys; sys.exit(b'\r\n' not in open(r'%t.h','rb').read())"
+// RUN: %clang_cc1 -E -C -o %t.i %t.h
+// RUN: %python -c "import sys; sys.exit(b'\r\r\n' in open(r'%t.i','rb').read())"
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Rinn wrote:

I feel like this is most likely a one off for checking \r. I see what you mean for split-file in some other tests, I'll make that change

https://github.com/llvm/llvm-project/pull/205084