Fix for a crash in the onchange handler of tree views on exit.

layout/xul/base/src/nsTreeFrame.cpp

@@ -265,3 +265,9 @@ void nsTreeFrame::FireChangeHandler(nsIPresContext& aPresContext)
   }
 }
 
+NS_IMETHODIMP 
+nsTreeFrame::DeleteFrame(nsIPresContext& aPresContext)
+{
+  ClearSelection(aPresContext);
+  return nsTableFrame::DeleteFrame(aPresContext);
+}

layout/xul/base/src/nsTreeFrame.h

@@ -41,6 +41,8 @@ public:
     
   void FireChangeHandler(nsIPresContext& aPresContext);
 
+  NS_IMETHOD DeleteFrame(nsIPresContext& aPresContext);
+
 protected:
   nsTreeFrame();
   virtual ~nsTreeFrame();