Tightening migration conditions. (Bug 11973614)

Change-Id: I6d7417b705227472d035f428cbec933cc6dbf2ce
diff --git a/src/com/android/launcher3/LauncherModel.java b/src/com/android/launcher3/LauncherModel.java
index d271976..4478e9b 100644
--- a/src/com/android/launcher3/LauncherModel.java
+++ b/src/com/android/launcher3/LauncherModel.java
@@ -227,8 +227,8 @@
         }
     }
 
-    boolean canMigrateFromOldLauncherDb() {
-        return mOldContentProviderExists;
+    boolean canMigrateFromOldLauncherDb(Launcher launcher) {
+        return mOldContentProviderExists && !launcher.isLauncherPreinstalled() ;
     }
 
     static boolean findNextAvailableIconSpaceInScreen(ArrayList<ItemInfo> items, int[] xy,