Devide the computeNodeBreadths function in sankeyLayout into several small functions (#10002)
Devide the computeNodeBreadths function in sankeyLayout into several small functions (#10002)

* fix(singleAxis): fix line width in singleAxis

* refactor(sankey): refactor some part of sankey layout

* refactor(sankeyLayout): Devide the computeNodeBreadths function in sankeyLayout into several small functions

ecomfe/echarts,apache/incubator-echarts,ecomfe/echarts,apache/incubator-echarts