Generate valid C++ for pure implemented dtors

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

src/Generator/Passes/SymbolsCodeGenerator.cs

@@ -401,7 +401,10 @@ namespace CppSharp.Passes
             WriteLine(" };");
             if (abstractDtor != null && !implementedDtors.Contains(abstractDtor))
             {
-                WriteLine($"{abstractDtor.Namespace.Name}::{abstractDtor.Name}() {{}}");
+                if (string.IsNullOrEmpty(abstractDtor.Body))
+                {
+                    WriteLine($"{abstractDtor.Namespace.Name}::{abstractDtor.Name}() {{}}");
+                }
                 implementedDtors.Add(abstractDtor);
             }
         }

tests/Common/Common.h

@@ -785,6 +785,16 @@ public:
     virtual ~PureDtor() = 0;
 };
 
+class PureImplementedDtor
+{
+public:
+    virtual ~PureImplementedDtor() = 0;
+};
+
+PureImplementedDtor::~PureImplementedDtor()
+{
+}
+
 DLL_API void va_listFunction(va_list v);
 
 struct DLL_API TestNestedTypes