[clang] [coroutine] Create coroutine body in the correct eval context (PR #78589)

[Haojian Wu via cfe-commits]

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@@ -0,0 +1,34 @@
+// RUN: %clang_cc1 -std=c++20 -ast-dump %s | FileCheck %s
+#include "Inputs/std-coroutine.h"
+
+// Github issue: https://github.com/llvm/llvm-project/issues/78290
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hokein wrote:

nit: we usually encode the github issue with `namespace GH78290 {...}`

https://github.com/llvm/llvm-project/pull/78589