[clang] [HLSL] Add ByteAddressBuffer, RWByteAddressBuffer and RasterizerOrderedByteAddressBuffer definitions to HLSLExternalSemaSource #113477 (PR #116699)

[Finn Plummer via cfe-commits]

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@@ -91,6 +94,18 @@ struct BuiltinTypeDeclBuilder {
       HLSLNamespace->addDecl(Record);
   }
 
+  CXXRecordDecl *finalizeForwardDeclaration() {
+    // Force the QualType to be generated for the record declaration. In most
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inbelic wrote:

Which of the added testcases would fail without this? Otherwise, could we add a testcase that would fail without this.

https://github.com/llvm/llvm-project/pull/116699