[clang] [CIR] Fix record layout for a union with no storage type (PR #213591)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,134 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o - | FileCheck %s --check-prefix=CIR
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erichkeane wrote:

We have tons of record-layout test files, why does this have to be a new one? 

https://github.com/llvm/llvm-project/pull/213591