Fixed nested abstract classes to get internally implemented.

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

src/Generator/Passes/GenerateAbstractImplementationsPass.cs

@@ -35,12 +35,12 @@ namespace CppSharp.Passes
 
         public override bool VisitClassDecl(Class @class)
         {
+            if (!base.VisitClassDecl(@class))
+                return false;
+
             if (@class.CompleteDeclaration != null)
                 return VisitClassDecl(@class.CompleteDeclaration as Class);
 
-            if (!VisitDeclaration(@class))
-                return false;
-
             if (@class.IsAbstract)
             {
                 foreach (var ctor in from ctor in @class.Constructors
@@ -50,7 +50,7 @@ namespace CppSharp.Passes
                 internalImpls.Add(AddInternalImplementation(@class));
             }
 
-            return base.VisitClassDecl(@class);
+            return @class.IsAbstract;
         }
 
         private Class AddInternalImplementation(Class @class)

tests/Basic/Basic.Tests.cs

@@ -11,6 +11,7 @@ public class BasicTests : GeneratorTestFixture
     public void TestUncompilableCode()
     {
         Assert.That(new ChangedAccessOfInheritedProperty().Property, Is.EqualTo(2));
+        Foo.NestedAbstract a;
     }
 
     [Test]

tests/Basic/Basic.h

@@ -15,6 +15,11 @@ private:
         Value2
     };
 public:
+    class NestedAbstract
+    {
+    public:
+        virtual void abstractFunctionInNestedClass() = 0;
+    };
 
     Foo();
     Foo(Private p);