[clang] [clang-repl] Fix assertion failure in CleanUpPTU() (PR #85378)

[Stefan Gränitz via cfe-commits]

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@@ -205,7 +205,7 @@ class StoredDeclsList {
     Data.setPointer(Head);
   }
 
-  /// Return an array of all the decls that this list represents.
+  /// Return the list of all the decls.
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weliveindetail wrote:

This is not an array (otherwise we could have done erase-remove)

https://github.com/llvm/llvm-project/pull/85378