[clang] [Clang][Sema] Fix incorrect rejection default construction of union with nontrivial member (PR #82407)

[Erich Keane via cfe-commits]

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@@ -188,3 +188,14 @@ static_assert(U2().b.x == 100, "");
 static_assert(U3().b.x == 100, "");
 
 } // namespace GH48416
+
+namespace GH81774 {
+struct Handle {
+    Handle(int) {}
+};
+// Should be well-formed b/c NoState has a brace-or-equal-initializer
----------------
erichkeane wrote:

```suggestion
// Should be well-formed because NoState has a brace-or-equal-initializer.
```


https://github.com/llvm/llvm-project/pull/82407