[clang] [Clang] Do not skip over `RequiresExprBodyDecl` when creating lambdas (PR #147764)

[Younan Zhang via cfe-commits]

================
@@ -1088,6 +1088,9 @@ void CXXNameMangler::mangleNameWithAbiTags(GlobalDecl GD,
     return;
   }
 
+  while (DC->isRequiresExprBody())
+    DC = DC->getParent();
----------------
zyn0217 wrote:

We had a similar while loop in TransformLambdaExpr, is that still needed?

Also I was going to ask if that high lambda patch could resolve these issues. But that still needs many iterations, so i think it's fine to just land the changes as is.

https://github.com/llvm/llvm-project/pull/147764