Created Unassigned: PropertyGrid native array support crashes (NullReferenceException) [20885]

When an object containing arrays is used with the PropertyGrid, modifying the collection crashes (adding an element). Arrays having null pointers also crashes the collection editor.

To reproduce:
class TestSubclass
{
public string m_test1;
public string Test1
{
get { return m_test1; }
set { m_test1 = value; }
}
public string m_test2;
public string Test2
{
get { return m_test2; }
set { m_test2 = value; }
}
}

class TestObject
{
TestSubclass[] m_array;
public TestSubclass[] Array
{
get { return m_array; }
set { m_array = value; }
}
}

public MainWindow()
{
InitializeComponent();
propGrid.SelectedObject = new TestObject();
}