cocos2d/cocos2d-x — pull request #7270 by Pisces000221 (2014-07-01 08:23:18+00:00)
Title: Fix a potential crash in Scheduler

Sometimes the program crashes if we use `ccSchedulerFunc` together with `SEL_SCHEDULE` in one scheduler.
The crash is caused by invalid `static_cast`, and now it's fixed by using `dynamic_cast`.

I'm not sure whether to add a test case for this. Please tell me. Thanks!