When reusing a panel that tracks a scrollView, the panel stays the scrollView's delegate

[datwelk]

When changing contentViewController on a FloatingPanel that has been set up to track a scrollView, that scrollView's delegate is not properly restored to the original delegate floatingPanel.userScrollViewDelegate, resulting in a crash when reusing it.

How to reproduce:

• create a floating panel with content view controller A that has a scroll view alpha with a delegate X (could be viewcontroller A)
• present the panel
• set the floating panel's content view controller to a view controller B with scroll view beta and a delegate Y (could be viewcontroller B)
• set the floating panel's content view controller back to view controller A
• note that the delegate of scroll view alpha is a FloatingPanel instance, instead of the original delegate X

Because FloatingPanel does not conform to UIScrollViewDelegate, whenever a delegate method is fired, the app will crash with an unrecognized selector sent to instance error message.