fix selection sync on client mode update (#1126)

fixes #1125

Author: epruesse

NEWS.md

@@ -4,6 +4,8 @@
 
 - Fixed a bug in `renderDT()`'s evaluation of `...` arguments when `quoted = TRUE` (#1130). 
 
+- Maintain selected columns/rows/cells upon re-render (thanks, @epruesse, #1125).
+
 # CHANGES IN DT VERSION 0.32
 
 - Fixed a bug that caused the column used for grouping with the RowGroup extension to change when relocated by the ColReorder extension (thanks, @isthisthat, @mikmart, #1109).

inst/htmlwidgets/datatables.js

@@ -1032,6 +1032,9 @@ HTMLWidgets.widget({
         updateColsSelected();
         updateCellsSelected();
       })
+      updateRowsSelected();
+      updateColsSelected();
+      updateCellsSelected();
     }
 
     var selMode = data.selection.mode, selTarget = data.selection.target;