Fixed the ostream type map which failed with pointers.

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

src/Generator/Types/Std/Stdlib.cs

@@ -315,7 +315,8 @@ namespace CppSharp.Types.Std
 
         public override void CLIMarshalToNative(MarshalContext ctx)
         {
-            var marshal = ctx.MarshalToNative as CLIMarshalManagedToNativePrinter;
+            var marshal = (CLIMarshalManagedToNativePrinter) ctx.MarshalToNative;
+            if (!ctx.Parameter.Type.Desugar().IsPointer())
                 marshal.ArgumentPrefix.Write("*");
             var marshalCtxName = string.Format("ctx_{0}", ctx.Parameter.Name);
             ctx.SupportBefore.WriteLine("msclr::interop::marshal_context {0};", marshalCtxName);

tests/STL/STL.h

@@ -36,4 +36,9 @@ struct DLL_API OStreamTest
     {
         stream << s;
     };
+
+    static void WriteToOStreamPtr(std::ostream* stream, const char* s)
+    {
+        *stream << s;
+    };
 };