left/right up now clears nav key down flag. Fixes an issue in TreeTable, possibly in normal Table too in some cases.

svn changeset:15067/svn branch:6.4

src/com/vaadin/terminal/gwt/client/ui/VScrollTable.java

@@ -5489,6 +5489,8 @@ public class VScrollTable extends FlowPanel implements Table, ScrollHandler,
      */
     private boolean isNavigationKey(int keyCode) {
         return keyCode == getNavigationUpKey()
+                || keyCode == getNavigationLeftKey()
+                || keyCode == getNavigationRightKey()
                 || keyCode == getNavigationDownKey()
                 || keyCode == getNavigationPageUpKey()
                 || keyCode == getNavigationPageDownKey()