Asks the delegate if the specified drawer should open.
Original signature is '- (BOOL)drawerShouldOpen:(NSDrawer *)sender'
Available in Mac OS X v10.0 and later.
- sender (NSDrawer)
- The drawer requesting permission to open.
YES if the drawer should open; NO to prevent the drawer from opening.
- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)