Fix a bug that causes curren selections to be overwritten when only 1 row is selected (#308)
Fix a bug that causes curren selections to be overwritten when only 1 row is selected (#308)

Co-authored-by: Mark <f1b5a91d4d6ad523f2610114591c007e75d15084@mesoica.com>
TonyGermaneri/canvas-datagrid,TonyGermaneri/canvas-datagrid