[llvm] [NFC] Move DroppedVariableStats to its own file and redesign it to be extensible. (PR #115563)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -108,4 +162,4 @@ class DroppedVariableStats {
 
 } // namespace llvm
 
-#endif
+#endif
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OCHyams wrote:

nit: whitespace

https://github.com/llvm/llvm-project/pull/115563