[clang] [APINotes] Add SWIFT_RETURNS_(UN)RETAINED support to APINotes (PR #118938)

[Egor Zhdan via cfe-commits]

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@@ -600,6 +603,13 @@ class FunctionInfo : public CommonEntityInfo {
 
   friend bool operator==(const FunctionInfo &, const FunctionInfo &);
 
+  FunctionInfo &operator|=(const FunctionInfo &RHS) {
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egorzhdan wrote:

This function needs to invoke the overload from its superclass as well, similarly to the existing `ObjCPropertyInfo::operator|=`

https://github.com/llvm/llvm-project/pull/118938