ExtendGlassFrame should be called when glass is enabled.

Hey Joe,

Below is the simple change that I needed to make in order to get the glassy style working again.

As I browsed through the history, though, I could see that punker76's changes were in this area as well. Apparently, he had a scenario where he was programmatically changing the GlassThickness to 0, then to X, and then to 0 again. In other words, I am not entirely positive that this is the change you want in general. It may make sense to have the _ExtendGlassFrame following the if/else ... but then you manually got rid of that change.

What is clear, however, is that the _ExtendGlassFrame call needs to run when glass is enabled.

Cory