[clang] [clang][Sema] Fix rejected-valid for explicit object parameters in dependent nested classes context (PR #209107)

[Corentin Jabot via cfe-commits]

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@@ -814,6 +814,7 @@ latest release, please see the [Clang Web Site](https://clang.llvm.org) or the
   would only use the first one). A new warning that diagnoses such declarations has been added to `-Wignored-attributes`.
   (#GH191829)
 - Fixed a crash in the constant evaluator when an ill-formed array new-expression whose bound could not be determined (e.g. `new int[]()`) was used in a constant expression. (#GH200139)
+- Fixed a rejected-valid case that used explicit object parameters in the context of dependent nested classes. (#GH136472)
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cor3ntin wrote:

```suggestion
- Fixed a rejected-valid case that used an explicit object parameter in an out-of-line definition of a nested class member. (#GH136472)
```

https://github.com/llvm/llvm-project/pull/209107