Stored the original class in its interface replacement used with multiple inheritance.

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

src/AST/Class.cs

@@ -141,6 +141,8 @@ namespace CppSharp.AST
             }
         }
 
+        public Class OriginalClass { get; set; }
+
         public bool IsValueType
         {
             get { return Type == ClassType.ValueType || IsUnion; }

src/Generator/Generators/CSharp/CSharpMarshal.cs

@@ -541,9 +541,8 @@ namespace CppSharp.Generators.CSharp
                 return;
             }
 
-            var qualifiedIdentifier = CSharpMarshalNativeToManagedPrinter.QualifiedIdentifier(@class);
-            if (@class.IsInterface)
-                qualifiedIdentifier = qualifiedIdentifier.Substring(1);
+            var qualifiedIdentifier = CSharpMarshalNativeToManagedPrinter.QualifiedIdentifier(
+                @class.OriginalClass ?? @class);
             Context.Return.Write("*({0}.Internal*){1}.{2}", qualifiedIdentifier,
                 Helpers.SafeIdentifier(Context.Parameter.Name), Helpers.InstanceIdentifier);
         }

src/Generator/Generators/CSharp/CSharpTypePrinter.cs

@@ -349,16 +349,11 @@ namespace CppSharp.Generators.CSharp
 
         public CSharpTypePrinterResult VisitClassDecl(Class @class)
         {
-            var nestedName = GetNestedQualifiedName(@class);
-
             if (ContextKind == CSharpTypePrinterContextKind.Native)
-            {
-                if (@class.IsInterface)
-                    nestedName = nestedName.Substring(1);
-                return string.Format("{0}.Internal", nestedName);
-            }
-
-            return nestedName;
+                return string.Format("{0}.Internal",
+                    GetNestedQualifiedName(@class.OriginalClass ?? @class));
+
+            return GetNestedQualifiedName(@class);
         }
 
         public CSharpTypePrinterResult VisitFieldDecl(Field field)

src/Generator/Passes/MultipleInheritancePass.cs

@@ -39,8 +39,7 @@ namespace CppSharp.Passes
             if (@base.CompleteDeclaration != null)
                 @base = (Class) @base.CompleteDeclaration;
             var name = "I" + @base.Name;
-            var @interface = (this.interfaces.ContainsKey(@base)
-                ? this.interfaces[@base]
+            var @interface = (interfaces.ContainsKey(@base) ? interfaces[@base]
                 : @base.Namespace.Classes.FirstOrDefault(c => c.Name == name)) ??
                              GetNewInterface(@class, name, @base, addMembers);
             return @interface;
@@ -53,7 +52,8 @@ namespace CppSharp.Passes
                     Name = name,
                     Namespace = @base.Namespace,
                     Access = @base.Access,
-                    IsInterface = true
+                    IsInterface = true,
+                    OriginalClass = @base
                 };
             @interface.Bases.AddRange(
                 from b in @base.Bases