[TableView, TreeView, TreeTableView] shift+PgUp/Down deselection is incorrect.

Run the app.
Click the first line.
Shift+PgDown
Shift+PgDown
Shift+PgUp
Only the first line is selected, so, Shift+PgUp deselected more than 1 page of content, which is wrong.

The symmetrical issue with PgDown.

Affected tests:
ControlsAutomatedTestSuite/javafx/scene/control/test/tableview/TableViewMultipleCellSelectionTest/testShiftPgUpDown
ControlsAutomatedTestSuite/javafx/scene/control/test/treetable/TreeTableMultipleSelectionTest/testShiftPgUpDown