hide launcher restore behind a flag.

enable with 'adb shell settings put secure launcher_restore_enabled 1'
before signing into wiped device

Bug: 12532845
Change-Id: I1471c39dac2e6e1412f7720b1ba8edf46273c593
diff --git a/src/com/android/launcher3/LauncherBackupHelper.java b/src/com/android/launcher3/LauncherBackupHelper.java
index a081c21..704d790 100644
--- a/src/com/android/launcher3/LauncherBackupHelper.java
+++ b/src/com/android/launcher3/LauncherBackupHelper.java
@@ -137,12 +137,15 @@
 
     private final Context mContext;
 
+    private final boolean mRestoreEnabled;
+
     private HashMap<ComponentName, AppWidgetProviderInfo> mWidgetMap;
 
     private ArrayList<Key> mKeys;
 
-    public LauncherBackupHelper(Context context) {
+    public LauncherBackupHelper(Context context, boolean restoreEnabled) {
         mContext = context;
+        mRestoreEnabled = restoreEnabled;
     }
 
     private void dataChanged() {