Fix latent bug that causes spurious ambiguous member lookups

This should have been fixed in #78673 but it was missed because it
requires a fairly complex trigger. The fix is to ensure that we never
try to clone inherited methods that are themselves inherited.

Author: j-hui

lib/ClangImporter/ClangImporter.cpp

@@ -6223,6 +6223,11 @@ TinyPtrVector<ValueDecl *> ClangRecordMemberLookup::evaluate(
 
       auto memberClangDecl = namedMember->getClangDecl();
 
+      // Skip this base class member if it isn't from recordDecl; this happens
+      // when this member was inherited.
+      if (memberClangDecl != recordDecl->getClangDecl())
+        continue;
+
       // Skip this base class if this is a case of nested private inheritance.
       //
       // BUG: private base class members should be inherited but inaccessible.