运行报错，不知是什么原因，哪位大神能帮帮看是什么原因。
CCDebug.js:149 Uncaught Error
at cc.assert (CCDebug.js:149:27)
at obj.on (eval at (quick_compile.js:238:32), :37:10)
at player_node.start (eval at (quick_compile.js:238:32), :124:20)
at eval (eval at createInvokeImpl (component-scheduler.js:219:57), 
65)
at CCClass._invoke (component-scheduler.js:224:13)
at CCClass.invoke (component-scheduler.js:140:14)
at CCClass.startPhase (component-scheduler.js:480:27)
at 102.cc.Director.mainLoop (CCDirector.js:887:37)
at callback (CCGame.js:632:26)
cc.assert @ CCDebug.js:149
