From 4f6ec4c7769cdb58e622e350857b58afe4d68ee8 Mon Sep 17 00:00:00 2001
From: Emmanuel Garcia <blasten@gmail.com>
Date: Mon, 27 Jul 2015 09:53:22 -0700
Subject: [PATCH] Fix #41

---
 iron-list.html | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/iron-list.html b/iron-list.html
index 190e484f..26fa31ec 100644
--- a/iron-list.html
+++ b/iron-list.html
@@ -233,7 +233,7 @@
     /**
      * A map between an item key and its physical item index
      */
-    _physicalIndexForKey: {},
+    _physicalIndexForKey: null,
 
     /**
      * The average scroll size
@@ -733,6 +733,7 @@
         this._physicalTop = 0;
         this._virtualCount = this.items ? this.items.length : 0;
         this._collection = this.items ? Polymer.Collection.get(this.items) : null;
+        this._physicalIndexForKey = {};
 
         // scroll to the top
         this._resetScrollPosition(0);