Picker: Only emit 'change' event when value is changed. (#9029)
Picker: Only emit 'change' event when value is changed. (#9029)

* isue#9027 picker emit only real user change

* issue#9027 date-picker emit change if user real change only

* issue#9027 date-picker emit change if user real change only

Leopoldthecoder/element-1,huguangju/element,Raganof/element,ElemeFE/element,Raganof/element,baiyaaaaa/element,Kingwl/element,ElemeFE/element,Leopoldthecoder/element-1,huguangju/element,baiyaaaaa/element,Kingwl/element