am 533e2728: Don\'t crash in onDestroy.  Not all ApplicationInfos have their icons loaded.

Merge commit '533e2728352fc55a14e4f1b689a916cbd7a58f12'

* commit '533e2728352fc55a14e4f1b689a916cbd7a58f12':
  Don't crash in onDestroy.  Not all ApplicationInfos have their icons loaded.
diff --git a/src/com/android/launcher2/AppInfoCache.java b/src/com/android/launcher2/AppInfoCache.java
index 65ae570..f89e3ab 100644
--- a/src/com/android/launcher2/AppInfoCache.java
+++ b/src/com/android/launcher2/AppInfoCache.java
@@ -148,7 +148,9 @@
     public static void unbindDrawables() {
         synchronized (sCache) {
             for (ApplicationInfo appInfo: sCache.values()) {
-                appInfo.icon.setCallback(null);
+                if (appInfo.icon != null) {
+                    appInfo.icon.setCallback(null);
+                }
             }
         }
     }