From a07e70ea3234147d1f2ac4d94ccffc780ffd54f3 Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Tue, 16 Apr 2013 23:40:48 +0200
Subject: [PATCH] Handle obscure edge case where deferred post render function
 receives a null frame state

---
 src/ol/renderer/maprenderer.js | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/ol/renderer/maprenderer.js b/src/ol/renderer/maprenderer.js
index 15276cca0d..adc4de270f 100644
--- a/src/ol/renderer/maprenderer.js
+++ b/src/ol/renderer/maprenderer.js
@@ -184,15 +184,14 @@ ol.renderer.Map.prototype.renderFrame = goog.nullFunction;
 
 /**
  * @param {ol.Map} map Map.
- * @param {!ol.FrameState} frameState Frame state.
+ * @param {ol.FrameState} frameState Frame state.
  * @private
  */
 ol.renderer.Map.prototype.removeUnusedLayerRenderers_ =
     function(map, frameState) {
-  var layerStates = frameState.layerStates;
   var layerKey;
   for (layerKey in this.layerRenderers_) {
-    if (!(layerKey in layerStates)) {
+    if (goog.isNull(frameState) || !(layerKey in frameState.layerStates)) {
       goog.dispose(this.removeLayerRendererByKey_(layerKey));
     }
   }