am ecb48385: Fix bug: moving items leaves workspace screens\' caches in bad state

* commit 'ecb48385312bc8307cb712b45087abd711fed678':
  Fix bug: moving items leaves workspace screens' caches in bad state
diff --git a/src/com/android/launcher2/CellLayout.java b/src/com/android/launcher2/CellLayout.java
index 73e0c8f..19e775b 100644
--- a/src/com/android/launcher2/CellLayout.java
+++ b/src/com/android/launcher2/CellLayout.java
@@ -973,6 +973,7 @@
             }
         }
         prepareCacheBitmap();
+        invalidateCache();
     }
 
     @Override