[llvm] [readtapi] Add Merge functionality (PR #72656)

[Juergen Ributzka via llvm-commits]

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@@ -32,6 +33,19 @@ class TextAPIWriter {
   static Error writeToStream(raw_ostream &OS, const InterfaceFile &File,
                              const FileType FileKind = FileType::Invalid,
                              bool Compact = false);
+
+  /// Get TAPI Text FileType of string input.
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ributzka wrote:

nit: I struggled a bit to read this at first try. Although I must admit, this was before I had my first sip of coffee and I just opened my laptop. Anyway, how does the following sound "Get TAPI FileType from the input string." instead?

https://github.com/llvm/llvm-project/pull/72656