FLEX-26808
CAUSE: DataGrid.grid_mouseDownHandler() committed the selection before checking whether the user was likely to begin a drag operation.
SOLUTION: Following the pattern in the spark List component, we're committing the selection on MOUSE_DOWN only if the user has clicked on an item which isn't selected yet, or the grid is not dragEnabled, or we're not in row selection mode (i.e. either GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS). But when it looks like the user might start a dragOperation, we're deferring the selection adjustment to the MOUSE_UP event (caught either in DataGrid.grid_mouseUpHandler() or in DataGrid.sandbox_mouseUpHandler() ).
NOTES:
-also removed some duplication between DataGrid.grid_mouseDownHandler() and DataGrid.removeMouseHandlersForDragStart().
-also corrected some asdocs @see references.
1 file changed
