[clang] [clang] remove ClassScopeFunctionSpecializationDecl (PR #66636)

[Erich Keane via cfe-commits]

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@@ -185,14 +185,11 @@ namespace SameSignatureAfterInstantiation {
 
 namespace PR22040 {
   template <typename T> struct Foobar {
-    template <> void bazqux(typename T::type) {}  // expected-error 2{{cannot be used prior to '::' because it has no members}}
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erichkeane wrote:

Can you restore the test here?  We still want to capture that behavior.  Additionally, despite them not being particularly interesting, please leave the ones from the 192-195 as well;

https://github.com/llvm/llvm-project/pull/66636