null pointer exceptions in wrapped mode when moving mouse wheel over annotations

Switch to wrapped mode when annotations are displayed and move the scroll wheel whilst the mouse is hovering over an annotation row with a tooltip.

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at jalview.gui.SeqPanel.mouseMovedOverAnnotation(SeqPanel.java:1187)
at jalview.gui.SeqPanel.mouseMoved(SeqPanel.java:1045)
at java.desktop/java.awt.AWTEventMulticaster.mouseMoved(AWTEventMulticaster.java:337)
at java.desktop/java.awt.Component.processMouseMotionEvent(Component.java:6680)
at java.desktop/javax.swing.JComponent.processMouseMotionEvent(JComponent.java:3360)
at java.desktop/java.awt.Component.processEvent(Component.java:6404)
at java.desktop/java.awt.Container.processEvent(Container.java:2263)