Assert recognizers not already added
Assert recognizers not already added

From iOS9 adding a gesture recognizer that is already associated with a view is an error and no longer associates it with the second view - it leaves it on the first.

See http://forum.cocos2d-objc.org/t/onenter-call-order-issue/17718/1 for circumstances in which this can (relatively easily) happen due to user code.

Assert prevents the problem and indicates a possible path to look at to fix it.
finthamoussu/cocos2d-objc,finthamoussu/cocos2d-objc,oxeron/cocos2d-objc,cocos2d/cocos2d-objc,finthamoussu/cocos2d-objc,oxeron/cocos2d-objc,finthamoussu/cocos2d-objc,cocos2d/cocos2d-objc