Pie legend color when color is function. Fix #2372
Pie legend color when color is function. Fix #2372

chenfwind/echarts,apache/incubator-echarts,ecomfe/echarts,100star/echarts,100star/echarts,xiayz/echarts,starlkj/echarts,willseeyou/echarts,chenfwind/echarts,xiayz/echarts,willseeyou/echarts,hexj/echarts,starlkj/echarts,hexj/echarts,hexj/echarts,willseeyou/echarts,apache/incubator-echarts,starlkj/echarts,ecomfe/echarts