esri/widgets/AreaMeasurement2D get an error when test in smartphone

[sdsSAINS]

I test the esri/widgets/AreaMeasurement2D in browser did not get any problem, but when i test in smartphone, i get an error. In smartphone, when i trigger the area tools and measure on the map, the second click i use double click it, then i get an error, 'Cannot read property 'measurement' of null'. You may also try this in sandbox and put it into smartphone mode, it will trigger the same error too. Any one could help to solve this problem?