Only implement abstract classes in C++ for ctors/dtors

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

src/Generator/Passes/SymbolsCodeGenerator.cs

@@ -59,8 +59,8 @@ namespace CppSharp.Passes
             }
 
             Class @class = (Class) method.Namespace;
-            bool needSubclass = method.Access == AccessSpecifier.Protected ||
+            bool needSubclass = (method.Access == AccessSpecifier.Protected ||
-                @class.IsAbstract;
+                @class.IsAbstract) && (method.IsConstructor || method.IsDestructor);
             string wrapper = GetWrapper(method);
             int i = 0;
             foreach (var param in method.Parameters.Where(

tests/CSharp/CSharp.h

@@ -1376,6 +1376,7 @@ public:
     virtual int size() const = 0;
     virtual int capacity() const = 0;
     virtual void* get(int n) = 0;
+    void hasParameterOnEmtptyCtor(int i) {}
 };
 
 class DLL_API InterfaceTester