diff --git a/mozilla/extensions/typeaheadfind/src/nsTypeAheadFind.h b/mozilla/extensions/typeaheadfind/src/nsTypeAheadFind.h
index c40f3150703..7cf50276b1e 100644
--- a/mozilla/extensions/typeaheadfind/src/nsTypeAheadFind.h
+++ b/mozilla/extensions/typeaheadfind/src/nsTypeAheadFind.h
@@ -120,6 +120,7 @@ public:
   // ----- nsIScrollPositionListener --------------------
   NS_IMETHOD ScrollPositionWillChange(nsIScrollableView *aView, 
                                       nscoord aX, nscoord aY);
+  virtual void ViewPositionDidChange(nsIScrollableView *aView) {}
   NS_IMETHOD ScrollPositionDidChange(nsIScrollableView *aView, 
                                      nscoord aX, nscoord aY);