Returns whether the specified view is collapsed.
Original signature is '- (BOOL)isSubviewCollapsed:(NSView *)subview'
Available in Mac OS X v10.0 and later.


- subview (NSView)
- The subview in the splitview.

YES if subview is in a collapsed state, NO otherwise.

- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)