Ext.Net.Core.ExtModel.CustomConfig.Add(string, JsObject) throws NULL exception

[fabriciomurta]

Found: 7.2.0 Ext.NET forums' thread: GridPanel Boolean data and Checkbox editor

The Ext.Net.Core.ExtModel.CustomConfig.Add(string, JsObject) method throws null reference exception if it is called to a component instance which its CustomConfig field is not explicitly initialized.

This may impose code pollution when the method could just initialize it if not so.

The following code reproduces the issue:

var col = new Ext.Net.CheckColumn()
{
    Text = "Really?",
    DataIndex = "really",
    Width = 50
};

col.CustomConfig.Add("editable", true);

To avoid the issue, two options are possible:

var col = new Ext.Net.CheckColumn()
{
    Text = "Really?",
    DataIndex = "really",
    Width = 50,
    CustomConfig = new Ext.Net.Core.JsObject()
};

col.CustomConfig.Add("editable", true);

```csharp
var col = new Ext.Net.CheckColumn()
{
    Text = "Really?",
    DataIndex = "really",
    Width = 50
};

col.CustomConfig = new Ext.Net.Core.JsObject
{
    { "editable", true }
};