Fix BaseButtons remaining pressed when hiding while pressed down
Created by: leonkrause
When a BaseButton is pressed down while being hidden (itself or one of its parents), it will remain pressed down. This easily leads to unexpected behavior when doing something like:
func _process( delta ):
if is_pressed():
get_parent().hide()
print( "Pressed & hidden!" ) # will be called every frame after pressing
For more info see https://github.com/okamstudio/godot/issues/2496#issuecomment-142167856 and this forum post. This change "unpresses" the button when hidden. Closes #2496 (closed). Depends on pull request #2533.