[llvm] [FileCheck] Remove unneeded unique_ptr. NFC. (PR #123216)

[Thomas Preud'homme via llvm-commits]

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@@ -180,8 +180,7 @@ struct FileCheckString;
 class FileCheck {
   FileCheckRequest Req;
   std::unique_ptr<FileCheckPatternContext> PatternContext;
-  // C++17 TODO: make this a plain std::vector.
-  std::unique_ptr<std::vector<FileCheckString>> CheckStrings;
+  std::vector<FileCheckString> CheckStrings;
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RoboTux wrote:

I cannot remember but I have a vague memory that it's related to the std::swap. I see that std::swap has noexcept since C++17, maybe that's the reason?

https://github.com/llvm/llvm-project/pull/123216